In a large mixing bowl, whisk together 3 cups of all-purpose flour, 1 teaspoon of salt, 1 teaspoon of cinnamon, 1/2 teaspoon of nutmeg, and 1 tablespoon of sugar until thoroughly combined.

Gently fold in 1 cup of pumpkin puree and 1 cup of active sourdough starter into the dry mixture.

Slowly pour in lukewarm water, about 1/2 cup, mixing until a sticky dough begins to form.

Turn the dough out onto a floured surface and knead for about 10 minutes until smooth and elastic.

Place the kneaded dough in a greased bowl, cover with a damp cloth, and let it rise for 4-6 hours.

Preheat your oven to 450°F (230°C).

After the first rise, gently punch down the dough and shape it into a loaf.

Cover the loaf with a towel and let it rise for another hour.

Once risen, place it in the preheated oven and bake for 30-35 minutes.

After baking, let the bread cool in the pan for 10 minutes, then transfer to a wire rack.