10:00 PM: In a clean glass jar, dissolve your 10g of starter culture into 45g of water. Stir in 45g of bread flour. Mix thoroughly, cover loosely, and let ferment at room temperature 74–78°F (23–26°C) overnight for 8 to 10 hours until it completely triples in volume and develops a bubbly surface.

8:00 AM – The Autolyse: In a large mixing bowl, whisk together the 400g of bread flour, 50g of whole wheat flour, and 3g of pumpkin pie spice. In a separate cup, whisk the 210g of water, 150g of pure pumpkin purée, and 20g of brown sugar together until completely smooth. Pour the wet pumpkin mixture into the dry flour mix and stir with a silicone spatula until a thick, bright orange, shaggy mass forms. Cover and let autolyse undisturbed for 45 minutes to fully hydrate.

8:45 AM: Pour all 100g of your active overnight levain over the rested pumpkin dough. Use your fingers to dimple and squeeze the levain deep into the matrix until fully incorporated. Let rest for 20 minutes.

Sprinkle the 9g of fine sea salt evenly over the surface. Pinch and knead the dough firmly for 3 to 5 minutes until the salt crystals fully dissolve and the dough gathers into a cohesive, soft ball.

Cover the bowl and let bulk ferment for 4 hours at a warm 78–82°F (25–28°C).

During the first 2 hours of bulk fermentation, perform 4 separate rounds of structural stretch-and-folds every 30 minutes. Wet your hands, lift the edges of the orange dough up high, and fold them cleanly over the center to build a strong gluten web. Let the dough rest completely undisturbed for the remaining 2 hours of the bulk proof until it feels light and airy.

1:00 PM – Shaping & Cold Retard: Tip the dough out onto a lightly floured workspace. Gently pull the outer edges inward toward the center to shape it into a round boule, flip it over so the smooth side faces up, and roll it firmly under your hands to build a tight outer skin.

Place the shaped boule seam-side up into a proofing basket dusted heavily with rice flour. Cover loosely and slide it into the refrigerator for a 5 to 12-hour cold retard to firm up.

5:30 PM: Position your heavy Dutch oven on the middle rack of your oven and preheat to 450°F (232°C) for at least 45 minutes.

The Pumpkin-Shape Tying Hack (Optional): Cut 4 equal lengths of baker's twine (about 24 inches each). Lay them across your counter in a star pattern, overlapping at the exact center point. Turn your chilled dough boule out directly onto the center of the strings. Bring the opposite ends of each string up over the loaf and tie them together loosely at the top center. Critical Note: Do not tie the strings tightly; leave them slightly loose so the dough has room to expand and burst outward around the string lines in the oven.

Use a sharp razor blade or lame to score decorative leaf or vine patterns onto the exposed skin sections between the strings.

Transfer the tied loaf carefully into the roaring hot Dutch oven. Drop the heavy lid on tightly to trap the steam and bake covered at 450°F (232°C) for exactly 20 minutes.

Carefully lift the lid off, lower the oven temperature to 425°F (218°C), and continue baking bare for an additional 20 minutes until the pumpkin segments turn a gorgeous, blistered deep gold color.

Remove from the oven and let cool for 20 minutes before carefully snipping and pulling the baker's twine away. Push a cinnamon stick or a real pumpkin stem into the top center hole for a perfect finish! Let cool completely on a wire rack before slicing.