Step 1

Heat oven to 425°F. Line 12 standard muffin cups with paper baking liners.

Step 2

In a large bowl, whisk together flour, granulated sugar, brown sugar, baking powder, baking soda, salt and cinnamon. In a separate medium bowl, use a spatula or wooden spoon to mix mashed bananas, melted butter, eggs and vanilla extract until combined. Pour the banana mixture into the flour mixture; whisk until just combined (batter will be slightly lumpy). Stir in chocolate chips.

Step 3

Divide batter evenly among prepared muffin cups (the cups will be quite full). Top each cup with a few more chocolate chips as desired. Bake for 5 minutes; reduce oven temperature to 350°F, then continue to bake muffins for 15 to 18 minutes or until the tops of the muffins are golden-brown and a toothpick inserted in the centers comes out clean.

Step 4

Cool muffins in pan for 5 minutes, then transfer to a cooling rack to cool completely.