Begin by turning your oven to 350°F (175°C) and let it preheat fully. Next, fetch an 8x8-inch baking pan. Grease it lightly and line it with parchment paper to make removing the brownies super easy later. 

Put your unsalted butter and preferred chocolate chips into a microwave-safe bowl, preparing them for melting. Heat the mixture in 20-second increments, giving it a good stir after each one, until it’s fully melted and smooth. Let them cool a bit.

Take your overripe bananas and mash them up well in a bowl using a fork or potato masher.

Now, add your cooled butter and chocolate mix to the mashed bananas. Then Mix in the sugar (granulated & brown), two eggs, and a teaspoon of vanilla extract until well combined.

Stir it thoroughly until all the ingredients are well combined and smooth.

In your second bowl, combine the cocoa powder, flour, baking powder, and a pinch of salt, sifting them together. Gradually incorporate this into your wet ingredients.

Throw chocolate chips if you want, for some extra texture and flavor. It’s totally up to you! For me I love that! 

Gently pour your batter into the prepared pan (with parchment paper), spreading it out evenly to create a smooth, uniform layer. 

Put it in the oven and bake for approximately 35 minutes until it's perfectly cooked. You’ll know it’s ready when a toothpick comes out with just a few moist crumbs (not wet batter!). 

Let the brownies sit in the pan and cool for about an hour before taking them out. Enjoy!