Preheat your oven to 350°F (175°C) and prepare a muffin tin with liners or lightly grease the tin.
Mash 3 ripe bananas in a large bowl. Add ¾ cup granulated sugar, 1 large egg, and 1/3 cup melted butter.
Stir in 1 teaspoon vanilla extract.
In a separate bowl, combine 1 1/2 cups all-purpose flour, 1 teaspoon baking soda, 1 teaspoon baking powder, and 1/2 teaspoon salt.
Gradually mix the dry ingredients into the banana mixture until just blended. Do not overmix.
Gently fold in 1 cup of chocolate chips.
For the streusel topping (optional), mix 1/2 cup brown sugar, 1/3 cup flour, 1/4 cup cubed butter, and 1 1/2 teaspoons cinnamon until crumbly.
Spoon the batter into the muffin cups.
Sprinkle with streusel topping if desired.
Bake for 20-25 minutes or until a toothpick inserted comes out clean.
Let the muffins cool in the tin for a few minutes, then transfer to a rack to cool completely.
Notes
Banana Size: This recipe uses medium bananas (6 to 7 inches long). You will need about 1 cup of mashed bananas.
Ripe Bananas: The riper the bananas, the sweeter and more flavorful your muffins will be. If your bananas aren't ripe enough, you can ripen them quickly by baking unpeeled bananas on a baking sheet at 300°F until the skins blacken (about 15-20 minutes).
Chocolate Chips: Feel free to use either milk, dark, or semi-sweet chocolate chips. You can also substitute the chocolate chips with nuts or dried fruit for a different flavor. If using mini chips, reduce to 3/4 cup.
Storage: These muffins can be stored in an airtight container at room temperature for up to 3 days or frozen for up to 3 months. To freeze, let the muffins cool completely and then store them in a freezer-safe bag or container.
Streusel Topping: The streusel topping is optional but adds a delightful crunch and sweetness. It can be omitted if preferred, or you can experiment with adding oats or nuts to the streusel mixture for a different texture.
Muffin Size: This recipe typically makes 12 standard-sized muffins. If making mini muffins, adjust the baking time accordingly – they will bake faster.
Substitutions Replace bananas with an equal amount of applesauce or mashed avocados. Swap granulated sugar with brown sugar for moister muffins.