Preheat the oven to 350F.
In a large bowl, mash the bananas. Add in the pumpkin puree, sugar, oil, vanilla, and eggs, and mix til combined.
Add in the flours, baking soda, salt, and spice, and mix just until it all comes together.
Spray a 9x5 loaf pan with nonstick spray, then pour the batter in. If desired, top with banana slices.
Bake until golden brown, and a toothpick inserted in the center comes out clean, 55-60 min.
Let cool slightly before cutting, and enjoy!