Preheat the oven to 350.
Prepare the "flax egg" and set aside. The flax egg works to mirror the consistency of eggs. It works great for vegan baking. Combine 1 tbsp of flax meal with 3 tbsp of water in a small bowl. Mix well and let sit for 10 minutes.
In a large mixing bowl, combine mashed bananas, oil, maple syrup, almond milk, vanilla, and flax egg (when it is ready). Mix very well.
Add in dry ingredients to the mix: coconut sugar, baking soda, baking powder, and gluten-free oat flour. Mix very well until a smooth batter is formed.
Fold in blueberries (fresh or frozen) and mix again.
Grease/line a standard muffin tin. Evenly distribute the batter in each vessel. Shake to even out. Sprinkle rolled oats on top of each vessel.
Bake for 25 minutes. Enjoy!