1. Combine Starter and Water: In a large mixing bowl, gently whisk together your active whole wheat sourdough starter with the warm water until the starter is mostly dissolved. The mixture should look milky and slightly bubbly.

2. Add Flour and Salt: Add the whole wheat bread flour to the wet mixture, followed by the salt. Use your hands or a sturdy spoon to mix everything until no dry streaks of flour remain and a shaggy dough forms. It will be sticky. Cover the bowl with a clean kitchen towel or plastic wrap and let it rest for 30 minutes (this is called autolyse, which helps the flour hydrate).

3. Perform Stretch and Folds: After the rest, begin the first set of stretch and folds. With wet hands, grab a portion of the dough from one side, stretch it upwards, and fold it over itself towards the center. Rotate the bowl a quarter turn and repeat this process 3-4 more times until you’ve gone all the way around. Cover and rest for 30 minutes. Repeat this stretch and fold process 3-4 more times, with 30-minute rests in between each set. The dough will become smoother and more elastic with each set.

4. Bulk Fermentation: After the final set of stretch and folds, cover the bowl and let the dough bulk ferment at room temperature (ideally 70-75F or 21-24C) for 6-10 hours, or until it has noticeably increased in volume (around 50-75%) and looks puffy and aerated. The exact time will depend on your room temperature and starter activity.

5. Shape the Loaf: Gently turn the dough out onto a lightly floured surface. Carefully pre-shape it into a round or oblong, letting it rest for 20-30 minutes. Then, perform a final shaping, creating tension on the surface of the dough. Place the shaped dough seam-side up into a floured banneton (proofing basket) or a bowl lined with a floured kitchen towel.

6. Cold Proof: Cover the banneton and place it in the refrigerator for 8-16 hours. This cold proof slows down fermentation, develops flavor, and makes the dough easier to score.

7. Preheat Oven and Dutch Oven: About an hour before you’re ready to bake, place your Dutch oven (with its lid) in your oven and preheat to 450F (232C).

8. Bake the Loaf: Carefully remove the hot Dutch oven from the oven. Gently invert the cold dough from the banneton into the hot Dutch oven. Score the top of the dough with a sharp razor blade or knife (a simple cross or a single slash works well). Cover the Dutch oven and bake for 30 minutes.

9. Finish Baking: Remove the lid from the Dutch oven and continue baking for another 15-20 minutes, or until the crust is deeply golden brown and the internal temperature reaches 200-210F (93-99C).

10. Cool Completely: Carefully remove the loaf from the Dutch oven and transfer it to a wire rack to cool completely for at least 1-2 hours before slicing. This step is crucial for the crumb to set and for the flavors to fully develop.