Preheat oven to 350°F. Grease a loaf pan and line it with parchment paper. Set aside.
In a large bowl, combine the mashed bananas, pumpkin puree, brown sugar, melted butter, eggs, and vanilla extract. Whisk until everything is mixed together.
Add in the flour, baking soda, baking powder, salt, cinnamon, nutmeg, and pumpkin pie spice. Whisk until everything is combined. Pour batter into your loaf pan.
In a medium-sized bowl, combine all of the streusel ingredients. Mix together with a fork until clumps form. Sprinkle evenly on top of the bread batter.
Bake for about 50-55 minutes.
Allow to cool before cutting into it. Enjoy!