Mix flour, salt, and instant yeast in a large bowl. Pour in warm water and stir until a shaggy dough forms.
Cover the bowl tightly and leave at room temperature for 12 to 18 hours until bubbly and doubled.
Turn the dough onto a floured surface, fold it over itself 4 to 5 times, and shape into a rough ball.
Rest the shaped dough on parchment for 30 to 45 minutes while preheating the oven and Dutch oven to 450°F.
Score the top with a sharp knife, then carefully lower the dough on parchment into the hot Dutch oven. Cover and bake 30 minutes.
Uncover and bake 10 to 15 more minutes until the crust is deep golden brown.
Cool on a wire rack for at least 30 minutes before slicing.