Preheat your oven to 350°F (175°C). This ensures that the bread bakes evenly.

Grease a 9x5 inch loaf pan with cooking spray or butter to prevent sticking.

In a large mixing bowl, mash the ripe bananas using a fork or potato masher until smooth. Ripe bananas provide natural sweetness and moisture.

Add the vegetable oil, eggs, water, and vanilla extract to the mashed bananas. Whisk together until well combined.

Gradually add the cake mix to the wet ingredients. Stir gently with a spatula until just combined. Be careful not to overmix, as this can make the bread dense.

If using, fold in the chopped nuts for added crunch.

Pour the batter into the prepared loaf pan, smoothing the top with a spatula.

Bake in the preheated oven for 55-60 minutes, or until a toothpick inserted into the center comes out clean. This indicates that the bread is fully cooked.

Once baked, remove from the oven and let the bread cool in the pan for about 10 minutes before transferring it to a wire rack to cool completely.

Slice the banana bread once it has cooled. Serve plain or with butter for an extra treat.

Store any leftovers in an airtight container at room temperature for up to 3 days, or refrigerate for up to a week.