In a large mixing bowl, combine 500g of bread flour and 350g of lukewarm water. Stir until a shaggy dough forms. Let it rest for about 30 minutes (this is called autolyse).

After the autolyse, add 100g of your active sourdough starter and 10g of salt into the bowl. Mix well until fully incorporated.

Begin kneading the dough on a lightly floured surface for about 10 minutes until smooth and elastic. Alternatively, you can use the stretch and fold technique in the bowl every 30 minutes for the next 2-4 hours.

Place the kneaded dough in a lightly oiled bowl, cover it with a kitchen towel, and let it rise at room temperature for 4-6 hours, or until it has doubled in size.

Once the dough has risen, gently remove it from the bowl and shape it into a ball. Let it rest on a lightly floured surface for about 30 minutes, covered with a towel.

After resting, shape the dough again into a tight ball and place it seam side down into a well-floured proofing basket or bowl. Cover it and let it rise for an additional 2-4 hours, or overnight in the refrigerator for a more intense flavor.

Preheat your oven to 450°F (232°C) for at least 30 minutes before baking. If using a Dutch oven, place it in the oven to preheat.

Once preheated, carefully transfer the dough onto a piece of parchment paper. Score the top with a sharp knife or bread lame to allow for expansion while baking.

Use the parchment paper to lift the dough into the Dutch oven (or onto the baking stone). Cover and bake for 30 minutes.

After 30 minutes, remove the lid (if using a Dutch oven) and bake for an additional 10-15 minutes, or until the crust is deep golden brown and the bread sounds hollow when tapped.

Let the bread cool on a wire rack for at least 1 hour before slicing.