1-Prepare the levain: mixing 42g white flour, 42g whole wheat flour, 84g water, and 8g ripe sourdough starter. Cover and keep it at a warm temperature for about 12 hours.

2-Bloom the cocoa powder: heating 24g canola oil until warm, whisk in the cocoa until thickened, then let it cool.

3-Mix for autolyse: mix 516g white bread flour, 120g high-protein white flour, 78g whole wheat flour, and 474g water 1 until just incorporated, then cover and rest for 30 minutes.

4-Add remaining ingredients to the autolyse dough: Add 16g superfine sugar, 14g fine sea salt, and the prepared levain to the autolyse dough, moisten with 40g water 2, and mix thoroughly until smooth and elastic, about 5 minutes.

5-Fold in the bloomed cocoa powder: by pinching and folding, then transfer to a container for bulk fermentation. Perform three sets of stretches and folds at 30-minute intervals over 4 hours at 74-76°F, adding 159g dark chocolate chunks and 159g dried sweetened tart cherries during the first set. After the last fold, let the dough rest covered.

6-Shaping and Proofing the Dough: Divide the dough into two rounds and let rest uncovered for 35 minutes. Shape each piece into a boule and place seam side up in proofing baskets. Proof the baskets covered and sealed in the refrigerator overnight for about 18 hours to enhance flavor and manageability.

7-Baking and Cooling: Bake at 450°F with a preheated baking surface or enclosed method, using steam for the first 20 minutes, then bake uncovered for another 30 minutes until the internal temperature reaches 204°F. Cool on a wire rack for 1-2 hours before slicing to allow flavors to settle.