The night before baking, combine 520 grams of all-purpose flour, 12 grams of salt, and 90 grams of sourdough starter in a bowl. Pour in 1 7/8 cups of water and mix with your hands until the dough is wet and sticky.

Cover the bowl with a towel and let the dough rest for 15 minutes. Then perform about 15 folds by grabbing a corner of the dough and folding it over itself, rotating the bowl with each fold.

Cover again and rest for another 15 minutes. Repeat the folding procedure to develop gluten strength and dough structure.

Cover the dough and leave it out at room temperature overnight to ferment and rise.

The next morning, the dough will be risen with visible air bubbles. Prepare a second bowl lined with parchment paper. Loosen the dough from its initial bowl, and fold it by lifting the center and tucking the ends underneath, rotating a quarter turn each time. Transfer the shaped dough to the prepared bowl and place it in the fridge for 5 hours.

Preheat your oven to 500°F (260°C) with a Dutch oven inside to heat.

Remove the dough from the fridge. Score the top with a sharp knife or blade, and transfer the dough into the hot Dutch oven using the parchment paper.

Bake the bread covered for 25 minutes.

Remove the lid and reduce the oven temperature to 450°F (230°C). Continue baking for another 12 to 14 minutes until the crust turns a deep golden brown and crisp.

Remove the bread from the oven and let it cool on a wire rack for at least 1 hour before slicing.