Preheat your oven to 350°F (175°C). Grease a standard 9x5 inch loaf pan with butter or non-stick spray. Line with parchment paper.

In a large mixing bowl, mash the bananas with a fork until smooth but slightly chunky.

Stir the melted butter into the mashed bananas. Add the egg, granulated sugar, brown sugar, vanilla extract, and salt. Mix well until combined.

Sprinkle the baking soda and cinnamon over the top and gently fold in the flour until no white streaks remain.

Pour the batter into the prepared loaf pan.

Bake for 50-60 minutes or until a toothpick inserted into the center comes out clean. The top should be golden brown.

Cool in the pan for 10 minutes before transferring to a wire rack.