Mixing and Bulk Fermentation

1. In a large mixing bowl, combine the bread flour, whole wheat flour, water, active sourdough starter, and salt. Mix until a shaggy dough forms.
2. Cover the bowl and let the dough rest (autolyse) for 30 minutes.
3. After the autolyse, perform a series of stretch-and-fold actions on the dough every 30 minutes for the first 2 hours. Wet your hands with water to prevent sticking. This helps develop gluten and strengthen the dough.
4. After the stretch-and-fold sessions, let the dough rest, covered, for an additional 2-4 hours at room temperature. During this time, perform an additional set of stretch-and-fold actions midway through the bulk fermentation.
5. Throughout the bulk fermentation, monitor the dough’s rise and fermentation activity. It should increase in volume, have a slightly domed shape, and display air bubbles.

Shaping and Final Proof

1. Prepare a work surface and lightly dust it with flour.
2. Gently transfer the dough onto the floured surface, being careful not to deflate it.
3. Divide the dough if making multiple loaves or shape it into a single loaf by gently folding the edges towards the center, creating tension on the surface.
4. Place the shaped dough in a proofing basket, seam-side up, and lightly dust the surface with flour. Cover it with a clean kitchen towel or plastic wrap.
5. Let the dough undergo its final proof at room temperature for 2-3 hours, or until it increases in volume and is visibly puffy.

Baking The Bread

1. Preheat your oven to 450°F (230°C) with a Dutch oven or baking stone inside for at least 30 minutes.
2. Carefully remove the proofed dough from the proofing basket.
3. Turn the dough out onto a piece of parchment paper and score the surface with a sharp knife or razor blade to allow for controlled expansion during baking.
4. Transfer the dough, parchment paper, and all, into the preheated Dutch oven or onto the hot baking stone.
5. Cover the Dutch oven with its lid or create a steamy environment in the oven by spraying water into the oven using a spray bottle.
6. Bake the bread covered for about 20 minutes, then remove the lid or open the oven to release steam.
7. Continue baking for another 20-30 minutes, or until the bread has a deep golden brown crust and sounds hollow when tapped on the bottom.
8. Remove the bread from the oven and let it cool completely on a wire rack before slicing.