Preheat the oven to 350°F.
Place all ingredients in a blender, breaking the bananas into pieces as you add them. Blend everything on high for a minute or two until a smooth batter forms.
Place 9 muffin cups into a muffin tin and pour the batter divided evenly between the cups; the amount of muffins will depend on the size of the bananas and type of oats (we like filling them as full for a tall muffin). Sprinkle the tops with extra oats and gently press them down.
Bake for about 30 to 33 minutes* until a toothpick comes out clean. Remove from the muffin tin and allow them to cool a few minutes before serving. Store refrigerated for up to 10 days or frozen for up to 3 months.
