In a large bowl, mix flour, salt, and yeast.
Pour in warm water and stir until a shaggy dough forms.
Cover and let rise at room temperature for 12–18 hours, until doubled and bubbly.
Turn dough onto a floured surface and gently shape into a round loaf.
Place on parchment paper and let rest 30 minutes.
Meanwhile, preheat oven to 450°F (230°C) with your Dutch oven inside.
Carefully transfer dough (with parchment) into hot Dutch oven. Cover with lid.
Bake for 30 minutes covered, then remove lid and bake another 10–15 minutes until deeply golden.
Remove bread and cool on a rack before slicing.