Preheat oven to 375 °F. (190 °C) Line a 12-cup standard muffin tin with paper liners or coat with nonstick spray; set aside.
To make the crumb topping by combining the brown sugar, flour, and cinnamon. Add the butter and with your hands, blend it until mixture resembles coarse cornmeal. Set aside.
⅓ cup packed brown sugar, 2 tablespoons all-purpose flour, ¼ teaspoon ground cinnamon, 1 tablespoon cold butter
In a large bowl, mix together flour, baking soda, baking powder, cinnamon and salt. In another bowl, beat together bananas, sugar, egg and canola oil. Stir the banana mixture into the flour mixture just until moistened.
1 ½ cups all-purpose flour, 1 teaspoon baking soda, 1 teaspoon baking powder, 1 teaspoon cinnamon, ½ teaspoon salt
In another bowl, smash the bananas with a fork then add the sugar, egg and canola oil. With a whisk or fork, mix all ingredients well. Stir the banana mixture into the flour mixture just until moistened.
3 bananas, 1 tsp. vanilla, ¾ cup white sugar, 1 egg, ⅓ cup canola oil, ⅓ cup packed brown sugar
Gently fold the banana mixture into the flour mixture and stir until combined. It may be a little lumpy due to the banana but that's okay.
Scoop the batter evenly into the muffin tray and sprinkle with reserved crumb topping.
Bake in preheated oven for 18 to 20 minutes, until a toothpick inserted into center of a muffin comes out clean.