Preheat oven to 350 degrees Fahrenheit.
Grease a 9x5-inch loaf pan.
Whisk flour, baking soda, baking powder, salt, cinnamon, nutmeg, and ginger in a medium bowl.
In another bowl, stir melted butter, granulated sugar, and brown sugar.
Mix in eggs until smooth.
Stir in mashed bananas, pumpkin puree, and vanilla extract.
Add the dry ingredients to the wet ingredients.
Stir until just combined.
Fold in chocolate chips or nuts if using.
Pour batter into the prepared loaf pan.
Spread the top gently.
Bake 55–65 minutes or until a toothpick comes out clean.
Remove from oven.
Cool in the pan for 15 minutes.
Transfer loaf to a rack.
Cool 20 minutes more before slicing.