01 -
Set oven to 350°F (175°C). Grease and line a 9x13-inch baking pan with parchment paper.
02 -
In a large bowl, mash the bananas. Add melted butter, granulated sugar, eggs, and vanilla extract. Beat until mixture is smooth and well combined.
03 -
In a separate bowl, mix all-purpose flour, baking soda, salt, and cocoa powder until evenly combined.
04 -
Gradually fold the dry ingredients into the wet mixture, stirring gently until just combined to avoid overmixing.
05 -
Stir in whole milk and chocolate chips if using, ensuring an even distribution.
06 -
Pour the batter into the prepared baking pan and spread it evenly with a spatula.
07 -
Combine brown sugar and ground cinnamon, then sprinkle evenly over the batter. Dot with small pieces of butter.
08 -
Bake for 25 to 30 minutes until a toothpick inserted in the center comes out with a few moist crumbs.
09 -
Let the brownies cool in the pan for 10 minutes, then transfer to a wire rack to cool completely. Slice into squares and serve.