01 - Preheat oven to 350°F. Line a standard 12-cup muffin tin with paper liners or lightly grease each well.
02 - In a large mixing bowl, whisk together pumpkin puree, mashed banana, eggs, oil, milk, and vanilla extract until the mixture is smooth.
03 - In a separate bowl, mix together flour, granulated sugar, brown sugar, baking soda, baking powder, salt, cinnamon, nutmeg, and ginger until thoroughly combined.
04 - Add dry ingredients to wet ingredients and stir gently until just combined. Avoid overmixing to ensure tender muffins.
05 - Fold in chopped nuts or chocolate chips if desired, distributing them evenly throughout the batter.
06 - Evenly divide the batter among the prepared muffin cups, filling each about three-quarters full.
07 - Place muffin tin in the oven and bake for 20 to 22 minutes, or until a toothpick inserted in the center of a muffin comes out clean.
08 - Allow muffins to cool in the pan for 5 minutes, then transfer them to a wire rack to finish cooling completely.