Creating your banana loaf with walnuts is straightforward when you follow these steps:

1. Preheat the Oven: Set your oven to 350°F (175°C) to prepare for baking.

1. Mash the Bananas: In a large mixing bowl, mash the ripe bananas with a fork until smooth.

1. Add Sugars and Butter: Mix in the granulated sugar, brown sugar, and melted butter until well combined.

1. Incorporate Egg and Vanilla: Add the egg and vanilla extract. Whisk until the mixture is smooth.

1. Combine Dry Ingredients: In a separate bowl, whisk together the flour, baking soda, salt, and ground cinnamon if using.

1. Mix Dry into Wet: Gradually add the dry ingredients to the banana mixture. Stir until just combined; take care not to overmix.

1. Fold in Walnuts: Gently fold in the chopped walnuts to distribute evenly throughout the batter.

1. Prepare the Loaf Pan: Grease a 9×5 inch loaf pan or line it with parchment paper.

1. Pour the Batter: Transfer the batter into the prepared loaf pan, smoothing the top.

1. Bake: Place in the preheated oven and bake for 60 minutes. A toothpick should come out clean when inserted into the center.

1. Cool: Once baked, let the loaf cool in the pan for about 15-20 minutes before transferring it to a wire rack to cool completely.