Feed the starter 6–8 hours before mixing so it’s bubbly and has doubled in size. If it floats in water, it’s ready.

In a large bowl, mix together the starter, warm water, pumpkin purée, and maple syrup until smooth. If using oil or butter, add it here.

Stir in the bread flour, whole wheat flour, cinnamon, nutmeg, and ginger until no dry spots remain. It should be shaggy, which is perfect.

Let the dough rest uncovered or lightly covered for 30–45 minutes to hydrate the flour.

Sprinkle salt over the dough and pinch and fold it in until fully incorporated; the dough will tighten slightly.

Over the next 2–3 hours, perform 3–4 sets of stretch-and-folds every 30 minutes to make the dough smoother and bouncier.

Allow the dough to rise at room temperature (72–75°F) until puffed by approximately 50% and jiggly with bubbles at the edges, about 3–5 hours.

Gently turn the dough onto a lightly floured surface and shape it into a round using a bench scraper. Rest it for 20 minutes.

Shape into a tight boule or batard and place seam side up into a rice-flour-dusted banneton.

Cover and refrigerate for 10–16 hours to improve flavor and make scoring cleaner.

Preheat a Dutch oven or steam setup to 475°F (245°C) for 45–60 minutes.

Turn the dough onto parchment and score a deep slash (1/2 inch) for expansion.

Load the dough into the hot pot, cover, and bake for 20 minutes.

Remove the lid, reduce the temperature to 450°F (232°C), and bake for an additional 20–25 minutes until deep mahogany with a crackly crust.

Cool the bread on a rack for at least 1 hour before slicing.