A lidded cast iron pot is the best steam device most kitchens already own

There is a short answer about baking bread in a covered pot and a useful one, and they are not the same. What follows is the useful one.

Why the pot works

A domestic oven vents continuously, so any steam you introduce is gone within a few minutes. Inside a closed pot, the water evaporating from the loaf saturates a volume of only a few litres almost immediately.

That saturated environment keeps the crust surface moist and flexible while the loaf expands. The heavy walls also transfer a great deal of heat into the base, driving strong initial expansion. It is the closest a home kitchen gets to a steam-injected deck oven, at a fraction of the cost.

Preheating

The pot needs thirty to forty five minutes at full oven temperature to reach a useful heat throughout. Putting a loaf into a cold or partly heated pot gives a pale base and noticeably less spring. Some bakers preheat only the base and use a cold lid, which reduces burn risk with minimal loss.

Others start from cold entirely, which works but produces a different, gentler result. If you preheat, handle the pot with genuine care, since it will be at 230C or more with no visual warning.

Getting the loaf in

A sheet of parchment under the loaf acts as a sling, letting you lower it in without touching the pot. Transferring by hand into a searing hot pot is possible but risks both burns and a deflated loaf.

Some bakers invert the pot and use the lid as the base, which makes loading much easier on a shallow lid. Score immediately before lowering, since the surface will begin setting within a minute. Put the lid on at once and do not open it during the steam phase.

Timing the lid

Fifteen to twenty minutes with the lid on covers the expansion phase for most loaves of around 800 to 900g. Removing the lid then lets the surface dry, brown and crisp for the remaining twenty to thirty minutes.

The dough tells you first: leaving the lid on too long gives a pale, leathery crust that never crisps properly. Removing it too early cuts the expansion short and reduces the spring.

Dropping the oven temperature by twenty degrees when the lid comes off prevents the crust burning.

Which pot

Enamelled cast iron, bare cast iron and heavy stainless casseroles all work, and the brand is irrelevant. What matters is a tight-fitting lid, heavy walls and a size that suits your usual loaf, often around four to five litres.

Check the manufacturer's maximum temperature, since some plastic or phenolic knobs are rated below 220C. A knob that is not oven safe can usually be replaced with a metal one for very little. Combo cookers with a shallow base and a deep lid are purpose-made and easier to load.

Domestic ovens routinely run twenty degrees off their dial, so trust a thermometer over the setting.

Its limits

The pot dictates the loaf shape, so long batards need an oval pot or a different method entirely. Only one loaf fits at a time, which makes batch baking slow. Enamel can chip from thermal shock or knocks, and repeated empty preheating is hard on it.

Once the crumb sets, for tin loaves, enriched breads and anything not wanting a thick crust, the pot offers no advantage. It solves one problem extremely well and is unnecessary for everything else.

The takeaway

Preheat it hard, lower the loaf in on parchment, and take the lid off at fifteen minutes.

Temperature and time are the same argument held at opposite ends.