Step 1: Prepare Your Starter. Make sure your sourdough starter is fed and bubbly. If it hasn't been fed in a while, give it a refresh 4-6 hours before you plan to start baking.
Step 2: Mix the Dough. In a large mixing bowl, combine 400 grams of bread flour and 300 grams of water. Mix until no dry flour remains. Let the mixture rest for 30 minutes.
Step 3: Add Salt and Starter. After the autolyse, add 11 grams of sea salt and 100 grams of your active sourdough starter to the dough. Mix well until everything is thoroughly combined.
Step 4: Bulk Fermentation. Cover the bowl with a damp cloth and let the dough rise at room temperature for 4-6 hours, or until it has doubled in size. Every 30 minutes during the first two hours, perform a series of stretch and folds.
Step 5: Shape the Dough. Once the dough has risen, gently turn it out onto a lightly floured surface. Shape it into a ball by folding the edges toward the center.
Step 6: Second Rise. Place the shaped dough into a well-floured proofing basket. Cover it with a cloth and let it rest for another 1-2 hours at room temperature, or refrigerate overnight.
Step 7: Preheat Your Oven. About 30 minutes before baking, preheat your oven to 450°F (230°C) with a baking stone or Dutch oven inside.
Step 8: Bake the Bread. Once preheated, carefully turn the dough out onto a sheet of parchment paper. Bake for 30-40 minutes, removing the lid after the first 20 minutes.
Step 9: Cool and Enjoy. Let the bread cool on a wire rack for at least an hour before slicing.