LoafLovers

Tag: shaping

  • The Big Tunnel Under Your Sourdough Crust: What Causes a Hollow Flying Crust and How to Fix It

    The Big Tunnel Under Your Sourdough Crust: What Causes a Hollow Flying Crust and How to Fix It

    You pulled a beautiful loaf out of the oven. The crust is dark and blistered, it sang as it cooled, and you were already composing the photo. Then you cut into it and the knife drops through a dense slab of crumb into a giant hollow cavern right under the top crust. The crust has lifted off like a dome over an empty room. It is one of the most deflating moments in home baking, partly because the outside looked so promising.

    Bakers call this a flying crust, or sometimes tunneling. It is not a random accident and it is not ruined bread — it toasts perfectly well. But it is a clear signal that something went wrong between the mixing bowl and the oven, and once you know how to read it, the fix is usually straightforward. Let’s work through the real causes, from most common to least, and exactly what to change for each.

    What a flying crust actually is

    During the first few minutes in a hot oven, your loaf does most of its expanding. The outside sets into a crust while the inside is still soft and full of gas that is rapidly expanding in the heat. In a healthy loaf, that expansion pushes the whole structure up evenly — the crumb and the crust rise together and stay fused.

    A flying crust happens when the crust sets before the crumb underneath it has finished rising, or when there is already a large weak void sitting just below the surface. The top skin firms up, the gas below keeps expanding and pushing outward, and because the crumb can’t rise into the crust, it tears away instead. The gas collects in that gap, inflating it into the hollow dome you sliced into. In almost every case the root problem is one of two things: the dough was not ready, or the surface was too tight and too fast to set. Let’s separate them.

    Cause #1: The loaf was underproofed

    This is the single most common cause of a hollow under the crust, and it surprises people because underproofed dough feels so firm and promising when you load it. An underproofed loaf still has enormous rising energy left in it. When it hits the heat, it lunges upward all at once in a violent burst of oven spring. The crust can’t keep up, the dough tears internally, and the gas pools in one big cavity rather than distributing into an even crumb.

    The giveaway: a flying crust from underproofing usually comes with a dense, tight crumb below the gap, sometimes with a compressed band near the bottom. The loaf looks like it tried to explode upward and left the lower half behind.

    The fix: give the dough more time in bulk fermentation. Watch the dough, not the clock — it should grow by roughly 50 to 75 percent, feel jiggly and alive, and show bubbles along the sides and surface. Use the poke test to judge readiness before you ever shape or bake. A cool kitchen slows everything down, so if your dough has been sluggish, it almost certainly needs longer than your recipe’s stated time.

    Finger poke test on proofing sourdough dough in a banneton
    The poke test tells you whether the dough has fermented enough to avoid a hollow, underproofed bake.

    Cause #2: Big gas pockets trapped during shaping

    If you shape your loaf too gently and leave large bubbles trapped just under the surface, those bubbles become the seed of a tunnel. In the oven they expand faster than the surrounding crumb, merge together, and lift the crust clean off. You’ll often see this as a flying crust in a loaf that is otherwise well fermented — the crumb below is open and nice, there’s just a giant pocket up top.

    The fix: degas more deliberately during pre-shaping. You are not trying to flatten the dough into a pancake, but you do want to pop the biggest bubbles and redistribute the gas evenly. When you do your pre-shape and bench rest, give the round a firm pat to release any balloon-sized pockets, then let it relax before the final shape. Even, small bubbles in, giant trapped voids out.

    Cause #3: The surface tension was too loose — or too tight

    Shaping is a balancing act, and both extremes can cause tunneling. If your final shape is too loose and slack, the dough skin is weak and the expanding gas finds the path of least resistance — straight up into a dome under the crust. If your shape is too tight, you create a drum-tight skin that sets instantly in the oven and refuses to let the crumb rise into it, which also forces a separation.

    The fix: aim for a smooth, taut surface with real but not desperate tension. The dough should hold a round shape and have a tight skin you could bounce a crumb off, without you fighting it or tearing the surface. If you’re not confident here, our guide to shaping a boule with real tension walks through the hand motions that build an even skin — the same skin that rises with the crumb instead of flying off it.

    Hands shaping sourdough into a tight boule with surface tension
    Degassing and reshaping with real tension removes the large gas pockets that later balloon into a tunnel.

    Cause #4: Slack, over-hydrated dough that can’t hold its structure

    Very high-hydration dough is wonderful for an open crumb, but it is also more prone to flying crust, especially for newer bakers. A slack dough has less internal strength to resist the oven’s push, so the structure gives way at its weakest point — the thin layer just under the setting crust. Add a slightly under-developed gluten network on top of that, and you have a loaf primed to tunnel.

    The fix: back the hydration down by five to ten percent while you dial in your process, and build more strength with an extra set or two of stretch-and-folds during bulk. You want the dough to pass a rough windowpane and to hold a defined edge when you turn it out. Once your shaping and proofing are reliable at a moderate hydration, you can push the water back up with far less risk of a cavern.

    Cause #5: The crust set too fast — steam and scoring

    Sometimes the dough is fine and the problem is purely in the bake. If the top of your loaf blasts to a hard crust in the first few minutes — too little steam, or a surface that dried out during a long uncovered proof — it locks into place before oven spring finishes, and the still-expanding crumb has nowhere to go but away from it.

    Scoring matters here too. A single shallow score at a low angle gives the gas a deliberate place to escape and expand, so it vents through the ear instead of ballooning blindly under the crust. Too shallow, too timid, or no score at all, and the pressure has to find its own exit — often as a hollow dome or a blowout bursting from the side.

    The fix: bake with plenty of steam for the first 20 minutes — a lidded Dutch oven is the easiest way to guarantee it — so the crust stays soft and extensible while the loaf is still rising. Score decisively with one confident slash at roughly a 30-degree angle to create a controlled weak point. A crust that stays pliable long enough will rise with the crumb and stay married to it.

    Scoring a sourdough loaf at a shallow angle with a lame
    A shallow, angled score gives trapped gas a controlled exit instead of ballooning under the crust.

    How to diagnose your own loaf in 30 seconds

    Next time you cut a flying crust, read the clues instead of guessing:

    • Hollow dome plus a dense, tight crumb below? Underproofed. Ferment longer, judge by feel and the poke test.
    • Hollow dome but a nice open crumb elsewhere? A trapped shaping bubble. Degas and reshape more deliberately.
    • Loaf also spread wide and flat? Too little surface tension or dough too slack. Tighten the shape, lower hydration, build more strength.
    • Great interior but a thick, hard, early-setting crust? A baking problem. More steam, a decisive score, don’t let the surface dry out.

    Most flying crusts I see come down to the same quiet pair: a loaf shaped a touch too gently and baked a touch before it was truly ready. Fix those two and the crust stops flying. You’ll know you’ve cracked it when you slice in and the crust is pressed tight against an even crumb, no cavern, no slab — just bread all the way through.

    Want to see exactly what a well-degassed shape and a proper score look like in real time? The full visual walkthrough of fixing a flying crust — shaping, poke test, and scoring — lives on the LoafLovers YouTube channel, and you can grab our free sourdough troubleshooting guide to keep the symptom-and-fix chart next to your bench. No perfect loaves, just the ones that finally stopped tunneling.

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  • Preshape and Bench Rest: The 20 Quiet Minutes That Fix a Loaf That Won’t Hold Its Shape

    Preshape and Bench Rest: The 20 Quiet Minutes That Fix a Loaf That Won’t Hold Its Shape

    It’s a demoralizing moment. Your dough rose beautifully in the bowl — puffy, alive, full of promise — and then you tipped it onto the counter to shape it and it fell apart. It spread into a sticky, shapeless puddle. It stuck to everything. Every time you tried to pull it into a tight ball it tore, or just slumped flat again the second you let go. You added more flour in desperation, made it worse, and ended up wrestling a loaf that was never going to hold its shape. If that’s you, you are almost certainly missing one quiet, unglamorous step that nobody put front and center when you were learning: the preshape, and the bench rest that follows it.

    It takes about twenty minutes, most of which is just waiting, and it’s the difference between a loaf that rises up and one that oozes out. Let’s walk through exactly what it is, why it works, and how to do it — the way you’d actually do it at the counter.

    A smooth preshaped round of sourdough resting on a floured bench with a bench knife beside it
    The preshape: a loose, smooth round set down to rest. This quiet step is where a cleanly shaped loaf is actually won.

    What preshaping actually is (and why skipping it wrecks shaping)

    Shaping sourdough well is really a two-stage process, not one. The preshape is stage one: after bulk fermentation, you turn the dough out and gently coax it into a loose, round ball — not tight, not fussy, just a rough round with a smooth top. Then you walk away and let it rest. Only after that rest do you do the real, final shaping.

    Here’s why skipping straight to final shaping goes so wrong. Fresh out of the bulk bowl, the dough is a disorganized, slack mass — the gluten strands are tangled and pointing every which way, and there’s no “grain” to work with. Trying to build a tight, structured loaf out of that chaos in one go means fighting the dough, overworking it, and tearing that delicate skin. The preshape does something simple and powerful: it gives the dough a gentle first organization and a rough, even round starting point. It turns a puddle into something with a shape you can then refine.

    Two doughs compared: one slack and spreading into a puddle, one holding a taut round dome
    Left: skipped the preshape, shaped a tearing puddle. Right: same dough, preshaped and rested first.

    The bench rest is where the real magic happens

    If the preshape sets the stage, the bench rest — that 15-to-30-minute pause afterward — is where the actual problem gets solved. And it solves two things at once.

    It lets the gluten relax. Right after you handle it, the dough is tense and springy — pull it and it fights back and tears. That tension is exactly why your final shaping was failing. During the rest, the gluten relaxes and becomes extensible: it will stretch smoothly instead of snapping. When you come back to shape, the dough cooperates. No tearing, no fighting.

    It builds a skin. As the preshaped round sits, its surface dries very slightly and sets into a smooth outer skin. That skin is what lets your final shape hold real tension — it’s the taut outer layer that makes a loaf rise up instead of spreading sideways. You literally cannot build good surface tension on a freshly turned-out, skinless blob. The rest creates the surface you need.

    So the bench rest isn’t dead time or an optional “nice to have.” It’s the step actively doing the work that makes the next step possible.

    How to preshape, step by step

    Keep it gentle — this is not where you build tight tension, just a loose round:

    • Turn the dough out gently onto a lightly floured counter. You want to preserve the gas and structure you built in bulk, so coax rather than dump.
    • Fold it into a loose round. Pull the edges up and into the center a few times to gather it, then flip it seam-side down.
    • Round it with a light drag. With cupped hands or a bench knife, drag the round in small motions against the counter. Here’s the trick most beginners miss: round it against a bare, unfloured patch of counter. That slight grip against the surface is what builds the smooth skin — flour underneath makes it slip and you get no tension at all.
    • Stop while it’s still loose. You’re aiming for a smooth-topped, roughly round ball that holds together — not a tight, perfect boule. Over-tightening now just means more tension to fight through later.
    Flour-dusted hands using a bench knife to drag and round dough into a taut ball on the counter
    Rounding against a bare patch of counter: the slight drag builds a smooth, tight skin without adding any flour.

    How long to rest — and how to read it

    The clock says 15 to 30 minutes, but the dough is the real guide. You’re waiting for the tense, springy round to relax and spread just slightly, losing a little of its height and its fight. Here’s how to read it:

    • Rested enough: the round has settled and relaxed a touch, and when you gently poke the edge it feels soft and extensible, not tight and rubbery. This is your window — shape now.
    • Not rested long enough: the dough still feels tight and snaps back fast; try to shape it and it’ll resist and tear. Give it another 10 minutes.
    • Rested too long: the round has gone completely flat and slack, spreading into a thin puddle with no structure left. It over-relaxed. Lightly re-round it to rebuild a little tension and shape soon after.

    A warm kitchen relaxes dough faster; a cool one slower. On a cold day lean toward the longer end, on a hot day check it sooner. Reading the dough instead of the timer is the whole skill, and the bench rest is a lovely low-stakes place to practice it.

    When it’s not only the preshape

    The preshape and rest will fix the vast majority of “won’t hold its shape” problems. But be honest about two neighbors, because a preshape can’t rescue a loaf that’s broken upstream:

    • Weak dough from the start. If your dough was slack and soupy before you ever tried to shape it, the problem may be underdeveloped gluten or flour that can’t carry your hydration. A rest helps extensibility, but structure has to be built during mixing and folding first — and your flour choice matters more than people think, as we cover in bread flour vs all-purpose for sourdough.
    • Over-fermented dough. If bulk went too far, the gluten has already broken down and nothing at the shaping stage will give you back structure you no longer have — it’ll spread and tear no matter how well you preshape. If your loaves keep collapsing the instant you turn them out or score them, read our guide to dough that deflates when you turn it out or score it to catch an over-proof before it reaches the bench.

    And one gentle note on handling: whether you’re preshaping a plain dough or one studded with add-ins, the same light touch applies — rough, overworked handling tears the structure you’re trying to protect, exactly as it does when folding inclusions into a loaf.

    Preshaped dough rounds resting under a cloth, one slightly relaxed and spread showing it is ready
    Rested right, the round relaxes and spreads just slightly — relaxed enough to shape, still holding structure.

    Put it together and your shaping transforms

    Here’s the full rhythm once it clicks: bulk finishes, you turn the dough out and give it a loose, gentle preshape, you let it rest fifteen to thirty minutes until it relaxes and skins over, and then you do your final shape — which now goes smoothly, builds real tension, and holds a tall, even dome. That taut, confident shape is what rises up in the oven instead of melting into a frisbee.

    The best part is how little effort it asks. Twenty mostly-idle minutes, slotted between two things you were already doing, quietly solving the single most common shaping frustration in sourdough. Skip it and you fight your dough every time. Add it and the dough starts cooperating — and you stop wondering why your loaves spread.

    If you’d like to actually see the preshape-round and the way a rested dough behaves under your hands — it’s one of those things that clicks instantly once you watch it — the full walkthrough lives on the LoafLovers YouTube channel, and our free sourdough troubleshooting guide gathers the shaping fixes in one place. Grab it, give your next bake the quiet twenty minutes, and watch your loaf finally stand up tall.

    A taut, evenly shaped sourdough boule resting seam-side up in a floured banneton
    Final shape over a rested preshape: taut, even, and holding its dome — ready to rise up instead of out.

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  • Why Does My Sourdough Stick to the Banneton? How to Stop Dough Tearing When You Turn It Out

    Why Does My Sourdough Stick to the Banneton? How to Stop Dough Tearing When You Turn It Out

    You did everything right. The starter was bubbly, the dough felt alive, bulk fermentation looked textbook, and the shaped loaf went into the banneton looking like a proper boule. Then this morning you tipped the basket over and… half the loaf stayed behind. A ragged crater where the smooth top should be, dough hanging off the coils like it never wanted to leave.

    It’s one of the most deflating moments in sourdough — an entire overnight proof, wrecked in the last two seconds. The good news: sticking is almost never bad luck. It’s a small number of fixable causes, and once you know which one is biting you, the fix takes minutes.

    Proofed sourdough dough clinging to and tearing on the coils of a cane banneton
    The heartbreak moment: a well-proofed loaf half-glued to the basket. Almost always a dusting or tension problem — not bad luck.

    First, what a banneton is actually doing

    A banneton (or brotform) isn’t magic — it’s a shaping mold that wicks a little moisture from the dough’s surface while it holds a round or oval shape during the final proof. That slightly drier skin is what gives you a clean release and a crust that scores well and springs in the oven.

    Sticking happens when that surface either never dries, or gets glued to the basket by wet flour paste. So the whole game is: keep the dough’s outer skin taut and lightly floured with the right flour, and don’t leave it in there long enough (or wet enough) to weld itself to the coils.

    Cause #1: You’re using the wrong flour

    This is the single most common culprit. If you dust your banneton with regular wheat flour and the dough is anything above a moderate hydration, the flour absorbs water, turns to paste, and gelatinizes into glue. It feels like you floured the basket, but you actually made wallpaper adhesive.

    The fix is white rice flour. Rice flour barely absorbs water and doesn’t gelatinize the way wheat does, so it stays gritty and slippery against the coils. Many bakers use a 50/50 mix of rice flour and their usual flour for a balance of grip and release, but if you’re fighting stickiness, go straight rice flour until it’s solved.

    Rice flour and wheat flour bowls beside a hand dusting a banneton
    Rice flour doesn’t absorb water and gelatinize the way wheat flour does — which is exactly why it releases so cleanly.

    Cause #2: You didn’t flour enough — or floured unevenly

    A light, polite dusting isn’t enough for a new or humid basket. You want a genuine, even coat that gets down into the grooves of the coils — those grooves are exactly where dough anchors itself.

    • Sprinkle rice flour generously, then tilt and rotate the basket so it coats the walls, not just the bottom.
    • Tap out the loose excess. You want the coils lightly filled, not a snowdrift.
    • Pay special attention to the sides and rim — a loaf that slumps outward grabs the walls first.

    If a spot looks bare and shiny, it will stick. Re-dust before the dough goes in, not after it’s already proofing.

    Cause #3: A brand-new basket that hasn’t seasoned

    New cane and rattan bannetons are thirsty and grippy. Out of the box, they stick to almost everything. They need seasoning — a few uses to build up a thin film of flour in the coils that acts as a permanent non-stick layer.

    To speed it up: mist the empty basket very lightly with water, dust it heavily with rice flour, and let it dry completely (overnight is ideal). Do this once or twice before the first bake. After a handful of loaves, most baskets release far more easily and need less flour each time. Never wash a seasoned banneton with soap — just knock out the crumbs and let it air-dry.

    Cause #4: Weak shaping — the skin is too slack to hold itself

    Even a perfectly floured basket can’t save a loaf with no surface tension. If your shaping leaves a loose, slack blob, the dough relaxes and spreads sideways into the coils during proof, pressing itself into every groove. More contact, more sticking — and a flatter loaf on top of it.

    Build a taut skin: after pre-shaping and a bench rest, do a final shape that drags the dough across the counter to tighten the outer surface until it feels like a smooth, drum-tight balloon. That taut skin holds the loaf up off the coils and gives the flour a dry surface to sit on.

    Baker shaping sourdough on a bench to build a taut, tight skin
    A taut outer skin holds its own shape — loose, slack dough slumps into the coils and grips.

    Cause #5: The dough is too wet or overproofed

    Two moisture problems, same result. Over-hydration for your flour and skill level means a wetter, stickier surface that no amount of rice flour fully tames — if you’re new to a recipe, drop the hydration 3–5% and dial it back up as your handling improves.

    Overproofing is sneakier. A loaf left too long in the final proof degrades its own gluten, goes slack and sticky, and welds to the basket. If your dough looks puffy and lifeless and sticks badly, you likely overshot the proof — shorten it, or cold-proof in the fridge, which firms the surface and makes turnout dramatically easier. A cold loaf straight from the fridge is the single easiest thing to release.

    The clean-release turnout: technique that seals the deal

    Even with everything right, a hesitant, wobbly turnout can tear a loaf. Do it in one confident motion:

    • Have your parchment (and Dutch oven lid or peel) ready before you touch the basket.
    • Lay the parchment over the top of the banneton, put your hand or a board on top, and invert the whole thing in one smooth flip.
    • Lift the basket straight up. If a spot clings, don’t yank — gently peel the coil back and let gravity do the rest.
    • Score immediately and get it into the oven while the surface is still taut.

    Cold dough, a well-floured seasoned basket, rice flour, and a decisive flip — stack those and sticking basically disappears.

    Sourdough loaf releasing cleanly from an inverted banneton onto parchment
    A clean, gentle turnout: quick, confident, and dead-center over the parchment.

    Your quick sticking-diagnosis checklist

    • Using wheat flour to dust? Switch to white rice flour today.
    • Light dusting? Go heavier and get into the coils; tap out the excess.
    • New basket? Season it a couple of times before you trust it.
    • Loaf slumping and spreading? Tighten your final shaping.
    • Wet, puffy, lifeless dough? Lower hydration or shorten the proof — and cold-proof for an easy release.
    Baked sourdough with a clean spiral coil pattern from the banneton on a blistered crust
    The reward: a crisp coil imprint on an intact crust, no torn skin or blowouts.

    Sticking feels like a betrayal after all that waiting, but it’s one of the most solvable problems on the whole sourdough journey. Fix the flour, fix the tension, respect the proof — and that gorgeous coil pattern lands on your crust instead of staying in the basket.

    Want to see the seasoning trick and a clean one-motion turnout in real time? The full walkthrough lives on the LoafLovers YouTube channel, and our free sourdough troubleshooting guide has the shaping and proofing fixes side by side — grab it and never lose another loaf to the basket.

    Sources & further reading:

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