1. Feed the sourdough starter 8–12 hours before baking and let it become bubbly.

2. In a bowl, mix water and starter until dissolved. Add flour, cocoa powder, and brown sugar and stir until no dry flour remains. Rest 30–45 minutes.

3. Sprinkle salt over the dough and fold by hand until evenly distributed and elastic.

4. Cover and bulk ferment for 3–4 hours, performing stretch and folds every 30 minutes for the first 2 hours.

5. During the final fold, gently incorporate chocolate chips and raspberries.

6. Shape the dough into a loaf and place seam-side up in a floured proofing basket.

7. Proof at room temperature 1–2 hours, then refrigerate overnight (8–12 hours).

8. Preheat oven and Dutch oven to 230°C. Transfer loaf to parchment, score the top, and bake covered for 25 minutes.

9. Remove the lid and bake 15–20 minutes more until crust is deeply browned.

10. Cool on a wire rack at least 1 hour before slicing.