Instructions:
- Autolyse: In a large bowl, combine all flours and 340g of the water. Mix just until no dry streaks remain. Cover and let rest for 1 hour.
- Incorporate Starter & Final Water: Add the active starter and the remaining 20g of water. Dimple with wet fingers to incorporate. Rest for 30 minutes.
- Salt & Butter Inclusion: Sprinkle the salt over the dough. If using butter, add it now. Knead gently using the pincer method or light stretch-and-folds until fully integrated (about 5 minutes).
- Bulk Fermentation & Strength Building: Over the next 3–4 hours, perform 4 sets of Stretch and Folds, spaced 30 minutes apart. The dough should become smooth and elastic.
- Pre-Shape: Gently turn the dough onto a lightly floured surface. Shape loosely into a round (boule). Rest for 20 minutes (bench rest).
- Final Shape: Gently shape the dough tightly into your desired form. Place seam-side up into your prepared banneton.
- Cold Proof: Cover the banneton tightly and place immediately into the refrigerator for 12–16 hours overnight.
- Preheat: About 1 hour before baking, place the Dutch Oven (with the lid on) into your oven and preheat to 500°F (260°C).
- Score & Load: Carefully remove the hot Dutch Oven. Gently turn the cold dough out onto a piece of parchment paper. Score the top decisively with a lame or razor.
- Lid-On Bake (Steam Phase): Carefully lift the dough using the parchment sling into the hot Dutch Oven. Place the lid on. Bake at 500°F (260°C) for 20 minutes.
- Lid-Off Bake (Crust Development): Reduce the temperature to 450°F (230°C). Remove the lid and continue baking for another 20–25 minutes, until the crust is deep golden brown.
- Cooling: Remove the loaf and cool completely on a wire rack for at least 2 hours before slicing to ensure the crumb sets properly.