Mix Starter: In a large bowl, combine 300g starter, 30g salt, and 600g warm water. Stir.
Add Flour: Mix in 920g flour until combined. Cover.
Rest & Fold: Let rest 10–20 minutes. Then pull and stretch each side of the dough (all 4 sides) and fold it over itself.
Bulk Rise: Cover and let rise for 6 hours at room temp.
Divide & Shape: Place dough on counter, cut in half. For each half:
Gently stretch into a large rectangle.
Fold bottom up, top down (like a letter).
Stretch side to side, fold right side in, then left side in.
Flip it over and shape into a smooth ball.
Final Proof: Place into baskets lined with flour. Cover and let rise 2–3 hours.
Preheat Oven: Place 2 Dutch ovens in the oven and preheat to 425°F.
Transfer & Score: I used a silicone sling to help lower the dough in easily! But you can also use parchment over each dough ball, then an upside-down plate. Flip and release dough. Score as desired.
Bake: Remove hot Dutch ovens. Lift silicone sling/parchment paper and lower dough into the pots.
Bake Covered: Cover and bake 30 minutes.
Finish Baking: Uncover and bake 10-20 more minutes.
Cool: Remove from Dutch ovens. Cool on wire rack.