Prep your pan and oven: Heat the oven to 350°F (175°C). Grease a 9x5-inch loaf pan and line it with a parchment sling for easy removal.

Mash the bananas: In a large bowl, mash the bananas until mostly smooth with a few small lumps. You want about 1 1/4 cups.

Whisk in the wet ingredients: Add melted butter, brown sugar, granulated sugar, eggs, and vanilla. Whisk until glossy and well combined.

Combine dry ingredients: In a separate bowl, whisk flour, baking soda, baking powder, salt, and cinnamon. This helps distribute the leavening evenly.

Bring it together: Add the dry mix to the banana mixture. Stir gently with a spatula just until the flour disappears. Do not overmix.

Fold in chocolate: Stir in the chocolate chips (and nuts, if using), leaving a small handful of chips for the top.

Fill the pan: Scrape the batter into the prepared pan. Smooth the top and sprinkle over the remaining chips for a pretty finish.

Bake: Place on the center rack and bake for 55–65 minutes. The loaf is done when a toothpick inserted in the center comes out mostly clean with a few moist crumbs (melted chocolate is fine).

Cool properly: Let the bread rest in the pan for 10–15 minutes. Lift it out using the parchment and cool on a wire rack for at least 45 minutes before slicing.

Serve: Slice with a serrated knife. Enjoy warm, at room temperature, or lightly toasted with a pat of butter.