Ingredients for the sponge:
- 1 cup active sourdough starter
- 1 1/2 cups lukewarm water
- 3 cups all-purpose flour
Ingredients for the dough:
- 1 tablespoon granulated sugar
- 2 1/4 teaspoons salt
- 2 cups bread flour
- 1 tbsp. water, optional
Ingredients to finish:
- 1 tbsp egg white lightly beaten with 1 tbsp water
- water in a spray bottle
Directions:
- In a large mixing bowl or the bowl of an electric mixer, combine the starter, water, and all-purpose flour. Mix together with a fork or wooden spoon until smooth. Cover with plastic wrap and let sit at room temperature for 4 hours. Transfer the bowl to the refrigerator and chill overnight, at least 12 hours.
- Remove the bowl from the refrigerator and add the sugar, salt, and bread flour to the sponge. Mix until a ball of dough begins to come together. If some of the dry ingredients will not incorporate into the dough, add the additional 1 tablespoon of water to moisten them. Continue kneading the dough (on low speed if using an electric mixer) until the dough is smooth and elastic, about 5-6 minutes.
- Form the dough into a ball and transfer to a large lightly oiled bowl, turning the dough once to coat in the oil. Cover with plastic wrap and let rise in a warm spot until doubled in volume, 3-4 hours.
- Line a baking sheet with a silicone baking mat or parchment paper. Transfer the dough ball to a lightly floured work surface and gently deflate the dough.
- Divide the dough into eight equal portions.
- Form each piece of dough into a ball, and tuck any loose edges or seams underneath. Place seam-side down on the prepared baking sheet. Repeat shaping with the other 7 pieces of the dough.
- Transfer the shaped dough to the prepared baking sheet. Cover loosely with lightly oiled plastic wrap. Let rise in a warm place until nearly doubled in volume, about 2-3 hours.
- Place a baking stone and preheat the oven to 425F.
- Just before baking, lightly slash the top of each ball using a sharp serrated knife. Brush the exposed surface of the loaves with the egg wash. Spray the loaves lightly with water.
- Slide the entire baking sheet onto the baking stone. Bake about 28-32 minutes, rotating the pan halfway through baking, until the crust is golden brown.
- Transfer the finished bread bowls to a wire rack and let cool at least 30 minutes before slicing and serving. To use as a bowl, make a circular cut on the top of the bowl and remove. Scoop out the inside of the bread to create a well for the soup.