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

Grease a 9x5 inch loaf pan with butter or non-stick spray to prevent the bread from sticking.

In a large mixing bowl, mash the ripe bananas with a fork until smooth. This releases the natural sugars and moisture, making the bread moist.

Add the melted butter to the mashed bananas and mix well.

Stir in the egg and vanilla extract until fully combined.

In a separate bowl, whisk together the flour, baking soda, and salt. This helps to evenly distribute the baking soda throughout the flour.

Gradually add the dry ingredients to the wet mixture, stirring gently with a rubber spatula until just combined. Be careful not to overmix, as this can make the bread dense.

Fold in the chopped walnuts if using.

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

Bake in the preheated oven for 60-65 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 it cool in the pan for 10 minutes before transferring to a wire rack to cool completely.