Step 1: Feed Your Starter - If your starter has been stored in the fridge, take it out and feed it with equal parts flour and water. Let it sit in a warm place for about 4 to 6 hours, or until it becomes bubbly and active.

Step 2: Mix the Dough - In a large bowl, combine 350 milliliters of water with the 100 grams of active starter. Stir until the starter dissolves in the water. Then add both types of flour — bread flour and whole wheat flour. Mix with your hands or a wooden spoon until everything is just combined.

Step 3: Rest (Autolyse) - Cover the bowl with a clean towel and let the dough rest for about 30 to 45 minutes.

Step 4: Add Salt - After the resting time, sprinkle the salt over the dough. Wet your fingers and gently squeeze the dough to mix in the salt evenly.

Step 5: Stretch and Fold - For the next 2 hours, perform a series of gentle stretches and folds every 30 minutes.

Step 6: Bulk Fermentation - After the last fold, cover the bowl and let the dough rest at room temperature for about 4 to 5 hours.

Step 7: Shape the Dough - Once the dough has doubled in size, it is time to shape it.

Step 8: Final Proof - Cover the dough and let it rest again for about 2 to 3 hours at room temperature, or overnight in the refrigerator.

Step 9: Preheat the Oven - Place a Dutch oven or baking pot inside your oven and preheat it to 230 degrees Celsius (450 degrees Fahrenheit).

Step 10: Score and Bake - Carefully transfer the dough onto parchment paper and make a shallow cut across the top. Place the dough into the hot pot, cover it, and bake for 20 minutes.

Step 11: Cool Completely - Remove the bread from the oven and let it cool completely on a wire rack before slicing.