1. Feed starter 4–8 hours before mixing until doubled, bubbly, and active.

2. Whisk starter and warm water in a large bowl; stir in pumpkin purée until smooth.

3. Add bread flour, all-purpose flour, salt, melted butter/oil, ½ tsp cinnamon, nutmeg, and ginger; mix to a shaggy dough.

4. Cover and rest (autolyse) 30 minutes.

5. Strengthen dough with 3–4 sets of stretch-and-folds every 30 minutes until smoother and elastic.

6. Bulk ferment 3–5 hours at 75–78°F until dough rises 50–75% and feels airy (slow spring on poke test).

7. Mix filling: brown sugar + 1½ tsp cinnamon. Prepare 1 tbsp softened butter.

8. Turn dough onto a lightly floured surface; roll to a 12×8 in rectangle.

9. Spread softened butter thinly; sprinkle cinnamon-sugar evenly. Roll up from a short side, pinch seam to seal.

10. Place seam-side down in a parchment-lined loaf pan or banneton. Proof 2–4 hours at room temp or refrigerate 8–12 hours.

11. Preheat oven to 425°F/220°C (preheat Dutch oven if using). Score loaf; bake 25 minutes covered, then uncover and bake at 375°F/190°C 20–25 minutes to 195°F internal.

12. Cool on a rack at least 1 hour before slicing. Serve plain, toasted, or with butter or cream cheese.