Preheat the oven to 350°F (175°C).

Grease and flour a 9×5-inch (or 8×4) loaf pan, or line it with parchment paper.

In a large mixing bowl, mash the ripe bananas until smooth, then add the eggs, melted butter or oil, and vanilla extract. Mix until well combined.

Gradually incorporate the yellow cake mix into the banana mixture, stirring gently until just combined. Be careful not to overmix.

If desired, fold in the chocolate chips and chopped nuts.

Pour the banana bread batter into the prepared loaf pan, spreading it evenly.

Place the loaf pan in the preheated oven and bake for 40-45 minutes. Check for doneness with a toothpick; it should come out clean.

Let the banana bread cool in the pan for about 10 minutes before transferring to a wire rack to cool completely.

Once cooled, slice the loaf into 12 servings and enjoy!