Preheat your oven to 350°F (175°C) and grease a 9x5-inch loaf pan.
In a large mixing bowl, combine the mashed bananas and melted butter. Mix until well combined.
Add the granulated sugar, eggs, and vanilla extract to the banana mixture. Stir until smooth.
In a separate bowl, whisk together the baking soda, salt, flour, and cocoa powder.
Gradually add the dry ingredients to the wet ingredients, mixing until just combined. Do not overmix.
Fold in the chocolate chips gently.
Pour the batter into the prepared loaf pan and smooth the top with a spatula.
Bake for 60-65 minutes, or until a toothpick inserted in the center comes out clean.
Allow the banana bread to cool in the pan for about 10 minutes before transferring it to a wire rack to cool completely.