01 - Preheat oven to 350°F. Grease a 9x5-inch loaf pan and line with parchment paper for easy release.
02 - Whisk together flour, cocoa powder, baking soda, and salt in a medium bowl until evenly distributed.
03 - In a large bowl, blend mashed bananas, melted butter, sugar, eggs, and vanilla extract until smooth.
04 - Gently fold the dry mixture into the wet batter until just combined, avoiding overmixing.
05 - Fold in chocolate chips and optional nuts evenly throughout the batter.
06 - Pour batter into prepared pan, smoothing the surface. Bake 50 to 60 minutes until a toothpick inserted in the center emerges with moist crumbs.
07 - Allow bread to cool in pan for 10 minutes, then transfer to a wire rack to cool fully before slicing.