Step 1: Prepare the Sourdough Starter

1. If you don’t already have a sourdough starter, mix 1 cup of flour and 1/2 cup of water in a jar. Stir until combined, cover loosely, and let it sit at room temperature for 24 hours.
2. Discard half of the starter and feed it with another 1 cup of flour and 1/2 cup of water. Repeat this process daily for 5-7 days until the starter is bubbly and active.

Step 2: Mix the Dough

1. In a large mixing bowl, combine 1 cup of active sourdough starter, 3 1/2 cups of bread flour, and 1 1/2 cups of water. Mix until no dry flour remains.
2. Cover the dough and let it rest (autolyse) for 30 minutes.

Step 3: Add Salt and Knead

1. After the autolyse, add 1 1/2 teaspoons of salt to the dough.
2. Wet your hands and gently knead the dough in the bowl for 5-10 minutes until it becomes smooth and elastic.

Step 4: Bulk Fermentation

1. Cover the dough and let it rise at room temperature for 4-6 hours, folding it every 30 minutes during the first 2 hours. To fold, grab one side of the dough, stretch it upward, and fold it over itself. Rotate the bowl and repeat on all sides.

Step 5: Shape the Dough

1. Lightly flour your work surface and turn the dough out onto it.
2. Gently shape the dough into a round or oval loaf, depending on your preference.
3. Place the shaped dough into a floured proofing basket or a bowl lined with a floured kitchen towel.

Step 6: Final Proof

1. Cover the dough and let it proof at room temperature for 1-2 hours, or refrigerate overnight for a slower, more flavorful rise.

Step 7: Preheat and Prepare

1. Preheat your oven to 475°F (245°C) with a Dutch oven or baking stone inside.
2. If the dough was refrigerated, let it sit at room temperature for 30 minutes before baking.

Step 8: Bake the Bread

1. Carefully transfer the dough to the preheated Dutch oven or onto the baking stone.
2. Score the top of the dough with a sharp knife or razor blade to allow for expansion.
3. Cover the Dutch oven with a lid (if using) and bake for 20 minutes.
4. Remove the lid and bake for an additional 20-25 minutes, or until the crust is deep golden brown.

Step 9: Cool and Serve

1. Remove the bread from the oven and let it cool completely on a wire rack before slicing.