In a large bowl, mix the flour, salt, and yeast.
Pour in the warm water and stir until a shaggy dough forms.
Cover the bowl with plastic wrap and let it sit at room temperature for 12 to 18 hours.
Preheat the oven to 450°F (230°C) and place a Dutch oven inside to heat for 30 minutes.
Turn the dough out onto a floured surface and shape it into a ball.
Carefully place the dough into the hot Dutch oven, cover with the lid, and bake for 30 minutes.
Remove the lid and bake for an additional 10-15 minutes until golden brown.
Cool on a wire rack before slicing.