Preheat your oven to 350°F and line a nonstick muffin tin with liners or use baking spray.
Mash the bananas in a medium bowl.
In a large mixing bowl, whisk together the flour, oats, coconut sugar, baking powder, baking soda, and salt.
In another bowl, beat the egg, then add almond milk, avocado oil, and vanilla. Stir in the mashed banana.
Combine the wet and dry ingredients until smooth, then fold in the blueberries.
Scoop the batter into muffin cups, filling each about ⅔ full.
Bake for 20 minutes or until a toothpick inserted in the center comes out clean.
Cool on a wire rack and enjoy warm or at room temperature.