Preheat your oven to 350°F (175°C).

In a medium bowl, mash the ripe bananas with a fork until smooth, leaving a few small chunks for texture.

Stir in the melted butter until well combined.

Mix in the sugar, beaten egg, and vanilla extract until everything is evenly incorporated.

In another bowl, whisk together the baking soda, salt, and flour.

Gently add the dry mixture to the banana mixture, stirring until just combined.

Fold in the walnuts if using.

Grease a 9x5 inch loaf pan or line it with parchment paper. Pour your batter into the prepared pan.

Place your loaf in the preheated oven and bake for about 60-65 minutes, or until a toothpick inserted into the center comes out clean.

When finished, remove the bread from the oven and let it cool in the pan for about 10 minutes. Then transfer it to a wire rack to cool completely.