A sweet, aromatic sourdough loaf filled with plump raisins and a buttery cinnamon‑sugar swirl. Soft, chewy crumb makes it perfect for toast, French toast or bread pudding.
Combine 35 g ripe sourdough starter, 35 g water and 35 g all‑purpose or bread flour in a small bowl. Stir until no dry bits remain, then cover and let sit at about 78 °F for 3–4 hours until doubled in size, bubbly and slightly aromatic.
In a large bowl, mix the prepared levain with 350 g of water, 450 g bread flour and 50 g whole wheat flour. Blend until a shaggy dough forms, then cover and rest for 30 minutes.
Add the remaining 10 g salt and 25 g water to the rested dough. Using wet hands, pinch, fold and slap the dough until it becomes cohesive and smooth (about 3–5 minutes).
Perform a series of 3–4 stretch‑and‑fold sets over roughly 2 hours, spacing each set 30 minutes apart. During the second set, sprinkle the 120 g raisins evenly over the dough and incorporate them with the fold. After the final fold, let the dough rest until it has puffed up about 30‑40 % (approximately 2–3 hours).
Mix together 55 g softened unsalted butter, 60 g brown sugar, 6 g ground cinnamon, 3 g flour and a pinch of salt until a thick paste forms. Set aside.
Flour a banneton (or a bowl lined with a kitchen towel) liberally with rice flour. Turn the dough onto a lightly floured surface and stretch into a 12 × 16‑inch rectangle. Spread about two‑thirds of the cinnamon filling over the surface, fold the sides to the centre, then spread the remaining filling on top. Roll the dough into a tight cylinder and place it seam‑side up into the prepared banneton.
Cover the shaped dough with plastic wrap or a shower cap and refrigerate for 12–20 hours (about 18 hours recommended).
Pre‑heat a Dutch oven inside the oven at 500 °F for 30 minutes. Remove the dough from the fridge, place parchment paper on top, flip onto the paper and score with a bread lame or sharp knife. Transfer the dough (with parchment) into the hot Dutch oven, cover and bake 25 minutes at 450 °F, then remove the lid and bake another 20 minutes at 400 °F until the internal temperature reaches about 205 °F.