01 -
Set oven to 350°F (177°C). Line a square 8x8 pan with parchment across the bottom and up the sides.
02 -
Microwave the butter for about a minute to melt it. Let it sit for 10-15 minutes to cool slightly.
03 -
Use a whisk to combine salt, flour, and baking powder in a bowl.
04 -
Blend the cooled butter with brown sugar until smooth, then whisk in the egg, mashed banana, and vanilla until it all comes together.
05 -
Slowly combine the dry ingredients into the wet bowl. Stir until just mixed. Gently fold in most chocolate chips, saving a handful for later.
06 -
Pour batter into the prepared pan and spread evenly. Scatter remaining chips on top. Bake for 30-35 minutes or until the middle is firm and a toothpick comes out clean.
07 -
Let it cool fully in the pan. Use the parchment to lift it out, then cut into squares.