preheat oven to 375 degrees and prepare mini muffin pan by adding paper liners.
In a large bowl, mix together 1 ½ cups flour, baking soda, baking powder and salt.
Using a fork, mashed the bananas in a bowl and set aside.
In another bowl add mashed bananas, sugar, egg and melted butter. Stir the banana mixture into the flour mixture just until moistened.
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.
Bake in preheated oven for 18 to 20 minutes, until a toothpick inserted into the center of a muffin comes out clean