Preheat the oven to 350°F (175°C). Grease a loaf pan.

In a mixing bowl, whisk together the sourdough starter, pumpkin puree, vegetable oil, brown sugar, and eggs until smooth.

In another bowl, combine the flour, baking soda, baking powder, cinnamon, nutmeg, and salt.

Gradually add the dry ingredients to the wet ingredients, mixing until just combined.

Pour the batter into the prepared loaf pan.

Bake in the preheated oven for 50-60 minutes, or until a toothpick inserted into the center comes out clean.

Let the bread cool in the pan for 10 minutes, then transfer to a wire rack to cool completely.