In a large mixing bowl, add the water and sourdough starter. Mix well to dissolve the starter.
Add the flour and salt to the bowl and mix well until a shaggy bread dough forms.
Cover the mixing bowl with a damp towel. Let the dough rest for 1 hour.
After one hour, perform a stretch and fold. To do that, take a side of the dough and stretch the dough up. Fold it over to the center of the bowl. Keep doing that until all sides of the dough are done.
Repeat the process 3 more times then cover with a damp kitchen towel and let the dough rise overnight or for 8-10 hours. This is the bulk fermentation.
The next day, flour your work surface with some flour and place the dough on the work surface. Shape the dough into a boule to increase the surface tension of the bread. Place the boule in a basket sprinkled with rice flour or all purpose flour and place it in the refrigerator covered with a clean kitchen towel for at least one hour.
Preheat the oven to 450 degrees F and place the Dutch oven in the oven as it preheats. Place the dough on a piece of parchment paper. Cut a deep slash on the top of the dough.
Carefully remove the Dutch oven from the oven and place the dough into the preheated Dutch oven. Bake for 30 minutes covered and then 30 minutes uncovered. Remove the bread from the oven once it is golden brown. For best results, allow the bread to cool before cutting into it.