Preheat oven to 375 degrees Fahrenheit. Grease a loaf pan with vegetable oil spray and set aside.
Mash bananas in a medium-sized bowl with melted coconut oil.
Add maple syrup, vanilla, and the egg and mix well.
Blend rolled oats in a blender or food processor to create a flour.
In a large bowl, add the oat flour, baking soda, cinnamon, and salt and stir to combine.
Pour banana mixture into the flour mixture and mix until just combined.
Add chocolate chips and any optional ingredients (such as walnuts) and mix in evenly.
Pour batter into the loaf pan and bake in the oven for 25 minutes or until a toothpick comes out clean when placed in the center.
Allow to cool slightly before slicing.