Creating this incredible Cinnamon Roll Banana Bread is straightforward with these simple steps:

1. Preheat Oven: Preheat your oven to 350°F (175°C). Grease a 9×5-inch loaf pan.

1. Mix Bananas and Butter: In a large mixing bowl, mash the ripe bananas with a fork. Stir in the melted butter until well combined.

1. Add Baking Soda and Salt: Sprinkle the baking soda and salt over the banana mixture and stir to combine.

1. Incorporate Sugar, Egg, and Vanilla: Mix in the sugar, beaten egg, and vanilla extract until smooth.

1. Blend in Flour: Add the flour gradually, folding it into the mixture until no dry flour remains. Be careful not to overmix.

1. Prepare Cinnamon Filling: In a small bowl, combine the cinnamon and brown sugar. This will be your filling.

1. Layer the Mixture: Pour half of the banana bread batter into the prepared loaf pan. Spread evenly. Then, sprinkle half of the cinnamon-sugar mixture over the batter.

1. Repeat Layers: Pour the remaining batter over the cinnamon mixture, then top with the rest of the cinnamon-sugar mixture.

1. Swirl: Use a knife to gently swirl the cinnamon mixture into the batter to create a marbled effect.

1. Bake: Place the loaf in the preheated oven and bake for 50-60 minutes or until a toothpick comes out clean.

1. Cool: Allow the bread to cool in the pan for about 10-15 minutes, then transfer to a wire rack to cool completely.