Preheat oven to 400f and line a mini muffin tin (spray liners to ensure they don't stick)
In a large bowl mash the bananas and then add the remaining wet ingredients. Mix well by hand.
Add in the dry ingredients and combine well. (there may be some banana clumps, that's ok)
Pour batter evenly into baking cups. Bake for about 15 minutes and let cool before removing.
Tip: add more crushed walnuts on top before baking or chocolate chips!