First, preheat your oven to 350 degrees F. In a mixing bowl, whisk together the pumpkin puree, mashed banana, eggs, milk, oil, maple syrup and vanilla extract.
Add the oat flour, almond flour, pumpkin pie spice, baking powder, baking soda and salt into the bowl. Combine with rubber spatula. If you are using chocolate chips or other mix-ins, fold them into the batter when the flour is almost all mixed. Don't overmix the batter. Mix until just combined. You can wind up with tough or gummy pumpkin banana bread that won't rise if you keep mixing.
Grease an 8x4 loaf pan or use parchment paper. Add the batter into the loaf pan (I added a sprinkle of pumpkin seeds on top) and bake at 350 degrees F for 50-55 minutes. Once the bread has been baking for about 50 minutes, I suggest inserting a toothpick into the middle of the bread. If the toothpick comes out pretty much clean, it's done.
Let the bread cool in the pan for 10 minutes. Then, gently remove it from the pan and place it on a wire cooling rack. Allow the banana bread to cool for at least 1 hour before slicing. Do not cut it while it’s still warm. It will fall apart.