In bowl of food processor, combine flour, rolled oats, sugar and cinnamon. Pulse once or twice to break down oats. Remove to medium bowl. Add butter and mix with a fork or pastry cutter until coarse and crumbly. Reserve.
For Muffins
Preheat oven to 350*F. Lightly grease muffin tin.
In a large bowl, combine flour, baking soda, cinnamon and salt.
In bowl of a stand mixer fitted with a paddle attachment, cream together butter and brown sugar and fluffy. Add in eggs in at a time, blending well between additions. Add yogurt and bananas, mixing until thoroughly combined.
Combine dry into wet mixture; stir just to moisten. DO NOT OVERMIX. Pour batter into prepared muffin tin, 3/4 full. Sprinkle each with topping.
Bake in preheated oven for 20-25 minutes, until a toothpick inserted into center of the muffin comes out clean. Let cool in pan for 5 minutes, then turn onto a wire rack to cool completely before serving.