Autolyse: In a large mixing bowl, combine the bread flour, whole wheat flour, and water. Mix with a dough scraper or your hands until no dry spots remain and a shaggy dough forms. Cover the bowl with a damp cloth or plastic wrap and let it rest for 30-60 minutes at room temperature. This step allows the flour to fully hydrate.

Add Starter & Salt: After the autolyse, add the active sourdough starter and fine sea salt to the dough. Mix thoroughly, using a 'pinching and folding' motion for 5-10 minutes, until the starter and salt are fully incorporated and the dough starts to feel a bit more cohesive. It might be sticky initially.

First Set of Stretch & Folds: Lightly wet your hands. Grab a portion of the dough from one side, stretch it upwards, and fold it over to the opposite side of the bowl. Rotate the bowl and repeat this process 3-4 times until you've folded all sides. Cover and let rest for 30 minutes.

Incorporate Inclusions: During the second or third set of stretch and folds (after another 30-minute rest), gently spread the orange zest and dried cranberries over the dough. Perform your stretch and folds as usual, ensuring the inclusions are evenly distributed throughout the dough.

Continue Stretch & Folds: Repeat the stretch and fold process every 30-45 minutes for a total of 4-5 sets over the next 2-3 hours. By the final set, the dough should be smoother, more elastic, and hold its shape better.

Bulk Fermentation: After the final set of folds, cover the bowl and let the dough bulk ferment at room temperature (ideally 72-78°F / 22-25°C) for another 2-4 hours, or until it has increased in volume by about 30-50% and shows signs of activity (small bubbles, domed surface). The total bulk fermentation time will be 4-6 hours, depending on your room temperature and starter strength.

Pre-shape: Gently scrape the dough out onto a lightly floured surface. Gently shape it into a loose round (boule) or oval (batard) using a dough scraper to create tension on the surface. Let it rest, uncovered, for 20-30 minutes to relax the gluten.

Final Shape: Lightly flour your banneton. Gently shape the dough into its final form (boule or batard). Transfer the shaped dough, seam-side up, into the floured banneton. Lightly dust the top with flour.

Cold Proof: Cover the banneton with a plastic bag or plastic wrap and refrigerate for 12-18 hours. This slow cold proof develops flavor and makes the dough easier to handle and score.

Preheat Oven & Dutch Oven: About 45-60 minutes before you're ready to bake, place your Dutch oven with its lid into your oven and preheat to 500°F (260°C).

Score & Transfer: Carefully remove the hot Dutch oven from the oven. Gently invert your cold dough from the banneton onto a piece of parchment paper. Using a bread lame or a very sharp knife, score the top of the dough with your desired pattern (e.g., a single long slash, a cross, or an elaborate design).

Bake Covered: Carefully lower the dough (still on the parchment paper) into the hot Dutch oven. Place the lid back on and bake for 20 minutes at 475°F (245°C).

Bake Uncovered: Remove the lid from the Dutch oven and reduce the oven temperature to 450°F (230°C). Continue to bake for another 25-30 minutes, or until the crust is a deep golden brown and the internal temperature reaches 200-210°F (93-99°C).

Cool: Carefully remove the bread from the Dutch oven and transfer it to a wire cooling rack. Allow the bread to cool completely for at least 2-3 hours before slicing. This is crucial for the crumb to set and for the best texture and flavor.