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Turn Your Oven Into a Sauna

Our usual approach to creating steam in a home oven doesn't produce steam for very long. We’ve come up with a more effective approach.

Professional bread ovens boast pressurized valves for injecting steam into the oven at the beginning of baking for three important reasons. For starters, a moist environment transfers heat more rapidly than dry heat does, allowing the gases inside the loaf to rapidly expand in the first few minutes of baking, ensuring maximum volume. At the same time, steam prevents the bread’s exterior from drying out too quickly, which would create a rigid structure that limits rise. Finally, moisture converts the exterior starches into a thin coating of gel that eventually results in the glossy, crackly crust that is a hallmark of a great artisanal loaf.

Our usual approach to creating steam in a home oven is to pour boiling water into a preheated loaf pan placed on the oven’s bottom rack, but the water doesn’t continue to boil for very long. Inspired by the superheated stones used to generate steam in Swedish saunas, we’ve come up with a more effective approach: using lava rocks. These irregularly shaped rocks (available at many hardware stores for use in gas grills) have a lot of surface area for absorbing and retaining heat, maximizing the amount of steam produced when boiling water is introduced.

1. Place a wide pan filled with lava rocks on the bottom oven rack beneath the baking stone (which we use to heat the bread’s interior as quickly as possible) and preheat. If you bake bread regularly, consider designating a pan for this purpose, since it will eventually get scratched.

2. Pour about 1/4 cup of boiling water onto the preheated rocks. Keep the oven door closed for one minute to create steam. Place the bread on the stone, pour another 1/4 cup of water over the rocks, and bake the bread as usual.

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