Steam plays a decisive role in achieving a crisp, glossy crust and robust oven spring
Enclosed vessels: Dutch ovens and roasters
A preheated Dutch oven or heavy covered roaster traps moisture released by the dough and the container itself, producing an internal humid environment similar to professional steam-injected ovens. America's Test Kitchen finds this approach highly effective for small-batch artisan loaves because the captured steam is immediate and concentrated, promoting a deep oven spring and blistered crust. Cast iron and enameled cast iron are preferred for their thermal mass; they require care to avoid thermal shock and can be heavy to handle.
Open-pan steam techniques
For bakers without a heavy covered pot, a metal steam pan or rimmed baking sheet filled with boiling water produces rapid vapor when placed on the oven floor. King Arthur Baking Company advises using a shallow metal pan rather than glass, because metal transfers heat quickly and generates steam more reliably. Some home bakers add ice cubes for sustained release of moisture; this yields slower, longer steaming but less immediate vapor peak. Care is required to avoid scalding from splashing water and to prevent sudden temperature changes that can crack fragile ceramic or glass pans.
Choice of pan affects cultural and environmental considerations. In regions where cast iron is common and durable cookware is passed through generations, Dutch ovens align with traditional hearth baking and long-term sustainability. In small urban kitchens or energy-conscious households, quick-steam metal trays use less energy and avoid heating a large mass of cookware.
Consequences of selecting an unsuitable pan include weak oven spring, dull or prematurely thick crust, and increased accident risk from water splashes. For most home bakers aiming for consistent artisan-style loaves, a heavy covered pot like a Dutch oven or a shallow metal steam pan used with boiling water offers the best balance of reliability, safety, and baking performance, as discussed by Jeffrey Hamelman at King Arthur Flour and tested by America's Test Kitchen.