I'm often asked if a Dutch oven or cast iron pan is critical to baking sourdough breads?
To answer that, it is important to understand the function of this pot.
A Dutch oven traps in steam that rises from bread as it bakes. Steam, during the first 15 minutes of baking is essential if you want to achieve a crispy artisan loaf, as the steam allows the bread to expand before it forms a crust completely. Baking the bread without steam will cause a crust to develop too quickly which can lead to a denser bread.
Though, whilst a Dutch oven is the best way to achieve this, it is not the only way.
You can create the steam needed to get crusty sourdough in your home oven; you’ll need two sheet pans and a hot oven for this. Place one sheet pan on the bottom shelf of your oven and preheat, the other pan goes under your bread. Once the oven is preheated, you can load in your bread and pour some water into that empty bottom pan. Make sure to close your oven door as quickly as you can, so the steam that is evaporating from the water in that bottom pan does not escape. After 15-minutes open the oven door and remove that water pan from the bottom shelf.
There you go; you created the process of steaming the bread that you usually get from a Dutch oven or Cast Iron Pan.