In a large mixing bowl, combine 3 cups of bread flour with 1 cup of water and 1 cup of active sour starter. Mix until a shaggy dough forms, then let it rest for 30 minutes.

Add 1 tablespoon of salt and knead the dough on a floured surface for 10 minutes until smooth and elastic.

Place the kneaded dough in a lightly oiled bowl and cover it with a damp cloth. Allow it to rise at room temperature for about 4 hours or until it has doubled in size.

After the first rise, gently turn the dough onto a floured surface. Shape it into a round loaf.

Let it rest for 20 minutes, covered with a cloth to prevent drying.

Place the shaped dough into a well-floured proofing basket or bowl lined with a floured cloth, seam side up. Cover it again and let it rise for 2 to 3 hours or refrigerate overnight.

Preheat your oven to 450°F (232°C) about 30 minutes before baking.

Carefully remove the hot Dutch oven, lift the dough into it, score the top, and bake for 30 minutes.

Remove the lid and bake for an additional 15-20 minutes or until the crust is deep golden brown.

Transfer the bread to a wire rack and let it cool for at least 1 hour before slicing.