Preheat Oven: Preheat oven to 350°F (175°C). Grease a 9x5-inch loaf pan or line it with parchment paper.
Mix Wet Ingredients: In a large bowl, whisk together pumpkin puree, brown sugar, granulated sugar, oil, eggs, and vanilla until smooth.
Combine Dry Ingredients: In a separate bowl, sift flour, baking soda, baking powder, salt, and pumpkin pie spice.
Combine Mixtures: Gradually add dry ingredients to the wet mixture, stirring until just combined. Avoid overmixing. Stir in water (or milk) to loosen the batter.
Fold in Add-ins (Optional): Gently fold in nuts or chocolate chips if using.
Bake: Pour batter into the prepared loaf pan. Bake for 55-65 minutes, or until a toothpick inserted in the center comes out clean.
Cool: Let the bread cool in the pan for 10 minutes, then transfer to a wire rack to cool completely.
