Combine the ingredients. Preheat the oven to 350 degrees. Mash the bananas in a large mixing bowl using a fork until there are no large chunks. Whisk the eggs with the smashed bananas, then add the oil and vanilla extract. Use a spatula to mix in the rolled oats, oat flour, brown sugar, cinnamon, baking soda, and salt. Stir until the mixture is just combined. Add the wet ingredients to the dry ingredients and stir until it is just combined.
Bake the banana bars. Grease a 9 X 9 baking dish with oil or butter on all sides. Pour the banana bar batter into the dish and place it in the oven on the middle rack. Bake the breakfast bars for 30 minutes. Remove them from the heat and allow them to cool to room temperature before glazing and slicing them.
Make the maple cream cheese frosting. Combine the room temperature cream cheese, confectioner's sugar, vanilla extract, and maple syrup until the texture is fluffy and smooth. Place the frosting in a piping bag and drizzle over the breakfast bars. Slice the breakfast bars into 12 equal portions and serve. Mangia!