Mix the flour, yeast, and salt in a bowl. Stir in the water to blend. What you’ll have is wet, shaggy, sticky dough, but not so wet as to be batter. Cover the bowl with a tea towel and let it rest in a warm place for at least 12, and up to 24, hours. It’s ready for the next step when the surface is dotted with bubbles.
Flour a work surface and dump the bread out onto it. Sprinkle over a little more flour and fold it once or twice. Cover with the tea towel and let rest 15 minutes.
Using only enough flour to keep the dough from sticking to your fingers, shape the dough into a ball. Coat a cotton towel with flour, wheat bran or cornmeal and lay the dough on it, seam side down, and dust with more flour, bran, or cornmeal. (You need quite a lot of flour because you want to be sure the dough doesn’t stick to the towel). Cover and let rise about 2 hours. When ready, the dough will be more than double in size.
Half an hour before the dough is ready, heat the oven to 450°F230°C. Put an 8-quart/2-litre cast iron pot or dutch oven (cocotte) inside to heat. When the dough is ready, remove the pot from the oven, turn the dough into it, seam-side up. (It will look messy, but this is OK). Shake the pan to settle the bread evenly. Cover with the lid, and bake 30 minutes. Remove the lid, and bake another 15 to 30 minutes, until the loaf is nicely browned. Cool on a rack.