In a large bowl, whisk together the flour, salt and yeast until mixed. Pour the warm water and use a spoon to stir until the dough forms a ball. The mixture will be wet and sticky to the touch.
Cover the bowl with plastic wrap and set aside in a warm place for 8-18 hours, until the dough rises and flattens at the top with bubbles. (The longer the better).
Heat the oven to 450°F. Once the oven is preheated, place a 6-quart Dutch oven with the cover on in the oven for 30 minutes.
Punch the dough down and flour a sheet of parchment paper. Transfer the dough to the parchment and with your hands floured, shape the dough in a ball. Sprinkle the top of the dough lightly with flour. Place some plastic wrap on top and let rest for 30 minutes.
Remove the Dutch oven from the oven. Remove the plastic wrap and transfer the dough with the parchment wrap beneath it. Cover the Dutch oven and bake for 45 minutes. Remove the cover and bake for another 10-15 minutes until the dough is golden brown on top. Cool slightly before serving.
Want to try this with whole wheat flour? You can absolutely make up to half of the total flour whole wheat if you want. Add an additional 2 teaspoons water per cup of whole wheat flour to prevent the dough from being too dry.
Do not skip using the parchment paper when transferring the dough as it is quite sticky.
Heating the Dutch oven ahead of time is important in creating the rustic texture of the bread.
You know the bread is done when it reaches around 209 to 210°F inside. Yes you can just insert a thermometer to confirm.