Preheat your oven to 177 °C (175 °C). Lightly grease an 8x8-inch square baking pan and line it with parchment paper, leaving a slight overhang on two sides for easy removal.

In a large mixing bowl, whisk together the mashed bananas, melted butter, light brown sugar, granulated sugar, egg, and vanilla extract until completely smooth and cohesive.

Sprinkle the all-purpose flour, baking soda, and salt over the banana mixture. Gently fold with a rubber spatula until just combined and no dry flour streaks remain.

Fold in the shredded coconut and 120 ml of chocolate chips until evenly dispersed throughout the batter.

Spread the batter evenly into the prepared pan, smoothing the surface with an offset spatula. Scatter the remaining 60 ml chocolate chips evenly over the top.

Bake for 32 to 38 minutes, or until a toothpick inserted into the center comes out clean or with a few moist crumbs, but no wet batter.

Transfer the pan to a wire cooling rack and let cool for at least 20 minutes before using the parchment sling to lift and slice into 9 squares.