In a large mixing bowl, combine the sourdough starter and water. Stir until well mixed. Gradually add the bread flour and salt, mixing with a wooden spoon or your hands until a shaggy dough forms.
Turn the dough out onto a lightly floured surface. Knead it for about 10-15 minutes, or until the dough becomes smooth and elastic. Alternatively, you can use the stretch and fold method: let the dough rest for 30 minutes, then stretch and fold it over itself a few times every 30 minutes for about 2-3 hours.
Place the kneaded dough back in the bowl and cover it with a damp cloth or plastic wrap. Let it rise at room temperature for 4-6 hours, or until it has doubled in size.
Once the dough has risen, gently turn it out onto a floured surface. Shape it into a round by folding the edges towards the center. Flip it over, seam side down, and let it rest for about 15 minutes.
After the rest, shape the dough again into a round or oval shape, depending on your preference. Place it seam side up in a lightly floured proofing basket. Cover it and let it proof for 1-2 hours, or until it has puffed up slightly.
About 30 minutes before you’re ready to bake, preheat your oven to 450°F (232°C). If using a Dutch oven, place it in the oven to heat up as well.
Carefully remove the hot Dutch oven from the oven. Gently turn the dough out onto a piece of parchment paper, then lift it into the pot. Cover with the lid and bake for 30 minutes. Remove the lid and bake for an additional 15-20 minutes, or until the crust is deeply golden brown.
Once baked, transfer the bread to a wire rack and let it cool completely before slicing. Enjoy your homemade sourdough bread!