In a large bowl, stir together flour, salt, and yeast. Add 2¼ cups lukewarm water. Stir with your hand until a sticky dough forms. Cover bowl with plastic wrap or a kitchen towel; let rise at room temperature overnight or up to 24 hours.
On a floured work surface, pat dough into a circular shape. (This is a wet dough.) Fold four edges in toward center; turn dough smooth side up. Sprinkle with flour, and cover with plastic wrap. Let rise at room temperature for 2 hours.
Place a 4- to 6-quart cast-iron Dutch oven in cold oven. Preheat oven to 500°F. Sprinkle top of dough generously with cornmeal. Using a large spatula, turn dough over; sprinkle with remaining cornmeal.
Place dough in preheated Dutch oven. (Use a wooden spoon to gently push dough into bottom of pan, if necessary.) Cover and bake for 30 minutes. Uncover and bake 15 to 20 minutes more. Let cool completely on a wire rack.
Recipe by Bake from Scratch at https://staging.bakefromscratch.com/dutch-oven-bread-variations/