01 -
Preheat oven to 350°F (177°C). Line 8x8 inch pan with parchment paper along bottom and sides.
02 -
Microwave butter until melted, about 1 minute. Cool for 10-15 minutes until warm.
03 -
Whisk together flour, baking powder, and salt in a bowl.
04 -
Whisk cooled butter with brown sugar, then add egg, mashed bananas, and vanilla until combined.
05 -
Stir dry ingredients into wet mixture gradually. Fold in most chocolate chips, reserving some for topping.
06 -
Spread in pan, top with remaining chips. Bake 30-35 minutes until center is set and toothpick comes out clean.
07 -
Cool completely before lifting from pan with parchment and slicing.