Banana crumb muffins

From: Julie...
1 1/2 cup all purpose flour
1 t. baking soda
1 t. baking powder
1/2 t. salt
3 banana's mashed
3/4 cup white sugar
1 egg, lightly beaten
1/3 cup melted butter
1/3 cup packed brown sugar
2 T all purpose flour 
1/8 t. cinnamon
1 T butter


Preheat oven to 375 degrees.  Lightly grease or line 20 muffin cups.  In a large bowl mix together 1 1/2 cup flour, baking soda, baking powder & salt. In another bowl beat banana's, sugar, eggs and melted butter.  Stir the banana mixture into the flour mixture just until moist.  Spoon into your prepared muffin pans.  Mix brown sugar, 2 T flour and cinnamon cut in 1 T butter. Crumble this together and sprinkle over the muffins. Bake for  18-20 min. check for doneness.