Refresh your starter (morning or night before): Feed your starter so it’s active and bubbly when you mix the dough. It should double in 4–8 hours and pass the float test. If it’s sluggish, give it one more feeding.

Mix the dough (autolyse): In a large bowl, whisk 25 g cocoa powder with 375 g warm water until smooth. Stir in 450 g bread flour until no dry spots remain. Cover and rest 30–45 minutes. This hydrates the flour and makes mixing easier.

Add the starter and seasonings: Add 100 g active starter, 35 g sugar, and 8 g salt. Drizzle in 15 g neutral oil. Squish and fold the dough by hand until everything is evenly combined and the dough looks cohesive. It will be tacky, not stiff.

Strengthen the dough (first hour): Over the next hour, do 3 sets of stretch-and-folds, spaced 20 minutes apart. With wet hands, pull one side up and fold it over, turning the bowl and repeating 4–6 times per set. This builds gluten without kneading.

Add chocolate: After the last fold, gently work in 120–150 g chocolate chips or chunks. If using extras like dried cherries (60–80 g), fold them in now. Avoid overworking, which can smear chocolate.

Bulk fermentation: Cover and let the dough rise at warm room temp (75–78°F / 24–26°C) for 3–5 hours, until puffed with small bubbles and about 50–75% larger. Cocoa can slow fermentation slightly, so watch the dough, not the clock.

Pre-shape: Lightly flour the counter. Turn out the dough, gently pat into a round, and fold the edges toward the center to make a loose ball. Rest uncovered for 15–20 minutes to relax.

Final shape: For a boule, flip the dough and tighten it into a round by tucking edges under and dragging gently to create surface tension. For a batard, pat into a rectangle, fold like a letter, and roll into a log.

Proof: Dust a banneton with rice flour. Place the dough seam-side up. Cover and refrigerate 10–16 hours for cold proofing. This improves flavor and makes scoring easier. You can also proof at room temp 60–90 minutes, but chilling is simpler for beginners.

Preheat and bake: Place a Dutch oven with lid in your oven and preheat to 475°F (245°C) for at least 30 minutes. Turn the chilled dough onto parchment, score the top with a sharp blade (a long central slash works well), and carefully lower it into the hot pot.

Steam bake: Bake 20 minutes covered. Reduce heat to 450°F (232°C), remove the lid, and bake another 20–25 minutes until the crust is set and the loaf sounds hollow. Aim for a deep brown, not black; cocoa makes the crust dark sooner, so rely on aroma and feel.

Cool completely: Move to a rack and cool at least 1–2 hours before slicing. The crumb sets as it cools. Cutting too early makes it gummy.