Preheat the oven to 180 C and line a muffin tray with muffin cases
Mash the bananas thoroughly and combine with the other wet ingredients (maple syrup, smooth peanut butter and vanilla extract)
In a separate large mixing bowl, combine all the dry ingredients (oat flour, baking powder, cinnamon and salt)
Pour the wet mixture into the dry and stir until combined
Then, spoon the mixture into muffin cases
Bake for 25 minutes (ovens may vary slightly - ensure a toothpick is removed clean)
Remove from muffin tray once cooked and cool on cooling rack (ensure fully cooled to ensure muffins don't fall apart)