10-12 hours before you mix your dough, place a clean jar or container on a kitchen scale and press “tare” so the weight reads “0.” To the jar add 100g water, 40g active starter, and 150g bread flour. Stir until no dry spots remain. Flip the dough in the jar because water gets stuck at the bottom. Let sit at room temperature 10-12 hours. The mixture will more than double.

In a medium or large bowl, add the whole biga (everything you mixed last night) and warm water (100-105°F). Incorporate the starter and water with your hands, breaking up as many lumps as possible. You won’t get it completely incorporated and that is fine.

Add bread flour and kosher salt to the starter mixture and mix with your hands. The dough is thick but sticky, so using your fingers like a whisk is easier.

Lightly oil a separate medium bowl and scrape the dough from the large bowl into the oiled bowl using a bowl scraper or silicone spatula. Remove as much dough from your hands as possible, cover the bowl with plastic wrap and set in a warm spot to proof until the only fold.

About 3 hours later, perform one set of stretch and folds using lightly oiled hands. Start on one side of the dough, slide your fingers under, stretch up and over. Rotate 90° and repeat. Rotate and fold until you’ve gone all the way around. Don’t worry about gluten development now. You can use oiled hands to help. Cover and let rest in a warm spot.

About 2 hours later, remove the plastic wrap, toss some bread flour on top of the dough because this is the stickiest part. Lightly dust the countertop, scrape the dough from the bowl using your scraper, and dump onto the floured surface. Using floured hands, fold each of the four corners into the center and flip seam-side down.

Using both hands, dipped in flour, pull the dough round towards you, rotate 90° and repeat until the top is tight and the boule sits tall. Toward the end the dough might start sticking. Simply dip in flour and continue. You can use a bench scraper, but I found that as long as I worked quickly, floured hands were best. This is the pre-shape.

Cover the boule with the overturned bowl and bench rest 15 minutes.

Flip the dough and repeat the folding and shaping. This is the final shaping.

Flip the dough upside down (seam side up) into a proof basket (banneton) dusted with rice flour, dust the dough lightly with rice flour, cover with plastic wrap and place in the warm place.

About 2–2½ hours later, preheat the oven to 450°F conventional or 425°F convection (with fan) with the Dutch oven inside (including the top). [See Recipe Notes or FAQ for baking without a Dutch oven.]

Once your oven is preheated, cut parchment slightly larger than the bottom of your Dutch oven. Remove the plastic wrap and gently loosen the edges using floured fingers. Turn the dough onto parchment.

Score the top with a razor blade. I recommend a square with overlapping edges, which allows the bread to rise up and out.

Working carefully, remove the Dutch oven from the oven. Close the door and remove the lid. Using the parchment edges, pick up the dough and place in the Dutch oven, not touching the sides. Replace the top and place back in the oven. Bake for 20 minutes.

After 20 minutes remove the lid and close the door. Lower the oven temperature to 425°F conventional or 400°F convection. Continue baking until golden brown, about 20 minutes more.

Remove the bread from the Dutch oven and cool on a wire rack. You can dump it out, carefully remove with your hands, or use tongs.