In a large bowl, combine flours, baking powder, salt and cinnamon. Set aside.
In another large bowl, combine mashed bananas, vegetable oil, sugars and vanilla. Stir in the egg, milk and nuts. Gently mix flour into the wet ingredients. Be careful not to over mix or you will have dense muffins.
Line a standard muffin pan with muffin liners. Fill each muffin liner about two thirds of the way full. Bake muffins for 14-16 muffins until a toothpick runs through and comes out clean.