Prepare the levain: Feed your sourdough starter using a 1:2:2 ratio of starter, flour, and water. Let it rise until tripled in size, around 5–6 hours.

Autolyse: In a large bowl, mix all flours and 240g of water until a shaggy dough forms. Cover and rest for 1 hour.

Mix the dough: Add 60g of peaked levain to the dough. Mix thoroughly by hand until the dough strengthens slightly. Cover and rest for 30 minutes.

Incorporate flavor: Add 6g salt, 15g extra water, chocolate peanut butter, and coconut sugar (or maple syrup). Mix well until fully combined.

First rest: Let the dough rest covered for 30–45 minutes, or until relaxed.

Bench fold: Perform one set of light bench folds to tighten the dough. Rest again for 30–45 minutes.

Lamination with add-ins: Gently stretch the dough out on a clean surface. Sprinkle chocolate chips and rum-soaked raisins evenly, then fold the dough back over itself.

Coil folds: After 45 minutes, perform one coil fold. Wait another 45 minutes and do a second coil fold. Let the dough rise until it increases about 50% in volume.

Shape and proof: Shape the dough into a tight round. Place it in a rice flour-dusted banneton. Let it sit for 15 minutes at room temperature. Cover and refrigerate overnight for 12–16 hours.

Preheat oven: The next morning, preheat oven to 250°C (480°F) for 1 hour with a Dutch oven or Challenger pan inside.

Score and bake: Remove dough from fridge, score using a bread lame. Place in the preheated Dutch oven with parchment paper and add 2–4 ice cubes beside the dough. Cover and bake for 20 minutes.

Continue baking uncovered: Remove the lid, reduce oven to 220°C (428°F) and bake for 10 minutes. Lower again to 210°C (410°F) for the final 10 minutes.

Cool the loaf: Turn off the oven, crack the door open, and let the loaf sit for 15 minutes. Transfer to a wire rack and cool completely before slicing.