How to Bake Sourdough in a Cast Iron Pot

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A cast iron pot is the closest thing to a steam-injected bakery oven you can put in your own kitchen. Lid on, it traps the loaf's own moisture as steam — and that steam is the secret behind a dramatic rise and a crackling, blistered crust. It's the single biggest upgrade most home bakers can make.

By Richard — I bake in cast iron long bread bakers (I've got five on the go at once) and nothing else I've tried at home comes close for oven spring and crust. The method below is exactly how I run them.

Why cast iron works so well

Two things make the difference. First, cast iron holds and radiates fierce, even heat — the base of your loaf hits a screaming-hot surface and springs upward instead of spreading. Second, and most importantly, the lidded pot traps the steam that escapes from the dough as it bakes. That trapped steam keeps the crust soft and stretchy for the first crucial minutes, letting the loaf expand to its full height before the crust sets. Take the lid off and that same crust dries, darkens and shatters into the bakery-style finish everyone's chasing.

My kit

I use cast iron long bread bakers — the long, lidded shape made for batards and baton-style loaves rather than round boules. The method is identical for a round cast iron Dutch oven if that's what you have; just shape a round loaf to match the pot.

Step by step

  1. Preheat the empty pot, lid on. Put the baker and its lid in the oven and bring it up to 240–250°C. Give it at least 30–45 minutes once up to temperature so the iron is fully heat-soaked — this matters more than people think.
  2. Score your loaf. I score mine cold, straight from the fridge — a firm, cold dough takes a clean, confident slash. One decisive cut down the length of a long loaf works best.
  3. Load it in. Lift the dough on its parchment (easiest and safest) straight into the screaming-hot baker, and get the lid back on immediately to seal the steam in.
  4. Bake with the lid ON, ~20 minutes. This is the steam phase — where all the oven spring happens. Resist every urge to peek; opening the lid lets the steam out and stops the rise dead.
  5. Lid OFF, drop to ~220°C, ~15–20 minutes. Now the crust browns and crisps. Take it to a deep golden-mahogany — darker than feels comfortable is usually right. It should sound hollow when you tap the base.
  6. Cool on a rack for at least an hour before cutting. The crumb is still setting inside; slice too soon and it goes gummy.
Be careful — that pot is dangerously hot. The baker and lid come out at 240°C+ and stay scorching for a long time. Use dry, heavy oven gloves, keep the handle area clear, and never set a hot lid down where someone might grab it.

Getting the most out of it

For extra spring

The trapped steam usually does it on its own, but if you want even more lift you can drop a couple of ice cubes (or a small splash of water) under the parchment as you load — just enough for an extra burst of steam under the lid.

Shape to the pot

Long bakers are made for batards and baton shapes — shape a tight, even log so it sits the full length of the pot. A round Dutch oven wants a round boule. Match the dough to the vessel and it'll spring true.

Don't open the lid early. The most common cast-iron mistake is peeking during the steam phase. Trust it — leave the lid on for the full first stretch and let the steam do its work.

Before you bake

A great bake starts long before the oven. Make sure your dough is well bulk fermented, properly shaped with good tension, and cleanly scored — the cast iron will reward all of it.

A strong, lively culture gives you the dough that springs like this. Ours is live, natural and ready to bake in about 2 hours.

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