Easy and delicious way to use up extra bananas. Also easy to make gluten free.
In a large bowl, mix together 1 1/2 cups flour, baking soda, baking powder and salt. Set aside.
Scoop batter into prepared muffin cups filling cups about 2/3 full.
In a small bowl, mix together brown sugar, 2 tablespoons flour and cinnamon. Cut in 1 tablespoon butter until mixture resembles coarse cornmeal. Sprinkle topping over muffins dividing evenly between muffins.
Let cool in pan about 5 minutes. Remove to wire rack to finish cooling.