Preheat oven to 400 degrees F (200 degrees C). Grease an 8x4-inch loaf pan with cooking spray.
Mix flour, brown sugar, and cinnamon together in a large bowl.
Mash bananas to the consistency of oatmeal. Mix in coconut oil, coffee, and vanilla extract. Pour over flour mixture; stir together with a wooden spoon. Pour batter into the greased pan.
Bake in the preheated oven until a toothpick inserted into the center comes out clean, 45 minutes to 1 hour. Cool for 20 minutes before slicing.