Preheat the oven to 375 degrees Fahrenheit. Line a 12-count muffin pan with muffin liners, then lightly spray the pan with nonstick cooking spray. Set aside.
Add 1 cup mashed bananas, 1 large egg, 1 teaspoon vanilla extract, 5 tablespoons melted unsalted butter, ¼ cup packed brown sugar, and ½ cup granulated sugar to a large bowl, and whisk until combined.
Whisk together 1 ½ cups all-purpose flour, 1 teaspoon baking soda, 1 teaspoon baking powder, ½ teaspoon salt, and ½ teaspoon ground cinnamon in a medium bowl. Add the flour mixture to the banana mixture and mix just until combined.
Scoop the batter into the prepared muffin pan until each well is filled ⅔-¾ of the way full.
Bake for 17-19 minutes, or until a toothpick comes out clean when inserted into the center of the muffins.
Notes
Updated May 27, 2025Storage Instructions: Store muffins in an airtight container at room temperature for up to 5 days, or freeze for up to 3 months. Thaw at room temperature or warm in the microwave for 30-60 seconds.