In a mixing bowl, mash the bananas until they're well broken down.
Add the cooled browned butter, brown sugar, granulated sugar, egg, and vanilla extract to the bowl.
Whisk the ingredients together until they're well combined.
Sift the all-purpose flour into a separate bowl.
Add the baking soda, salt, and cinnamon powder to the flour and mix until well combined.
Gradually add the dry ingredients to the wet ingredients and mix until a thick batter forms.
Fold in the semi-sweet chocolate chips.
Preheat the oven to 350°F (180°C).
Line a loaf pan with parchment paper.
Pour the batter into the prepared loaf pan and top with chopped walnuts and additional chocolate chips.
Bake for 50-55 minutes, or until a toothpick inserted into the center of the bread comes out clean.
