Preheat oven to 350°F. Spray mini muffin tins well with non-stick spray or line with mini paper liner cups.
In a medium bowl, whisk together flour, baking powder, baking soda, salt, and ground cinnamon. Set aside.
Mash bananas until smooth.
In separate bowl, beat sugar and oil together until blended. Add eggs, sour cream, mashed bananas, and vanilla. Beat on medium speed 1 minute until smooth.
Stir in flour mixture and beat until blended.
Fill muffin cups almost to the top. Sprinkle Turbinado sugar on top.
Bake 15 minutes or until toothpick inserted into center is dry. Do not over bake.