Step 1: Preheat the Oven - Start by preheating your oven to 350°F (175°C) to ensure even baking.
Step 2: Prepare the Muffin Tin - Line a muffin tin with paper liners or grease it lightly with non-stick spray.
Step 3: Mix Dry Ingredients - In a mixing bowl, whisk together the flour, baking soda, baking powder, salt, and cinnamon.
Step 4: Combine Wet Ingredients - In a separate bowl, mash the bananas until smooth. Add the white sugar, beaten egg, and melted butter, then mix until well combined.
Step 5: Combine Wet and Dry Ingredients - Pour the wet ingredients into the bowl with the dry ingredients and stir until just combined.
Step 6: Prepare the Crumb Topping - In a small bowl, combine the brown sugar, 2 tablespoons of flour, and 1/8 teaspoon of ground cinnamon. Cut in 1 tablespoon of butter until it resembles coarse crumbs.
Step 7: Fill the Muffin Tin - Spoon the batter into the prepared muffin tin, filling each cup about 2/3 full.
Step 8: Add Crumb Topping - Sprinkle the crumb topping evenly over each muffin.
Step 9: Bake - Bake in the preheated oven for 18-22 minutes, or until a toothpick inserted comes out clean.
Step 10: Cool and Enjoy - Allow the muffins to cool for 5 minutes in the tin before transferring them to a wire rack.
