In a large bowl dissolve yeast in water. Add flour and salt; stir to a shaggy, sticky dough. Cover with plastic wrap; rest 12–18 hours at ~21°C (70°F) until surface dotted with bubbles.
Turn dough onto lightly floured surface; sprinkle with a little flour. Fold over on itself twice; rest 15 minutes covered.
Shape gently into a ball using minimal flour. Place seam-side down on floured towel (or parchment) dusted with flour/bran/cornmeal. Cover with towel; rise 1–2 hours until doubled and fingerprint stays.
At least 30 minutes before baking, heat oven to 246°C / 475°F with heavy covered pot (6–8 qt) inside.
Carefully remove hot pot; invert dough into pot seam-side up (it may look uneven). Cover; bake 30 minutes.
Uncover; bake 15–20 minutes more until richly browned (internal temp ~96°C / 205°F). Cool on rack at least 1 hour before slicing.