This delicious boule, made with gluten free sourdough starter, has a substantial crust and a gorgeous open crumb! Millet, sorghum and brown rice flours combine to create an incredible loaf perfect for sandwiches (or slathered in butter!).
Mix millet starter, flour and water in a glass bowl. Allow to sit for 2–4 hours until bubbly and active.
Thoroughly whisk psyllium fiber, sorghum and brown rice flour in the bowl of a standing mixer. Insert the dough hook attachment and add presoak starter mixture. on low speed. Add honey, then slowly add warm water and egg whites. The dough will be sticky, but not wet or dry. Switch mixer to medium speed and knead for 5 minutes. Allow to rest in the mixer for 10–15 minutes. Add the salt and baking powder and knead again for a few minutes, making sure the mixture is well blended.
Spray a medium-sized bowl with olive oil, then sprinkle in a little white rice flour. Place dough in the bowl and cover with a towel. Place in a warm place to proof until doubled in size, 10–12 hours.
Once doubled, place a medium cast iron skillet in the oven and preheat to 500°F. Once the oven is preheated, carefully pull the pan out of the oven and turn the temperature down to 450°F. Gently pour the dough ball onto the flat part of the cast iron pan, sprinkle the top of the loaf with white rice flour, slash the top with a sharp knife or blade, splash a little water into the side of the pan, cover with a lid and place it in the oven. Bake for 40 minutes covered. Uncover and bake for an additional 10–15 minutes, or until golden brown.
You can also bake this uncovered for 50–55 minutes. Place a pan of water in the oven to create steam, much like the lid would do.
Allow to cool for 1–2 hours on a wire rack before cutting.
