Preheat your oven to 350°F (175°C) and grease a loaf pan.

In a mixing bowl, mash the ripe bananas with a fork until smooth. Mix in the melted butter until well combined.

Stir in the baking soda and pinch of salt to the banana mixture.

Add the sugar, egg, and vanilla extract, mixing well to incorporate.

Gently stir in the flour until just combined; do not overmix.

In a separate bowl, combine the tablespoon of flour with the cinnamon and 1/4 cup of sugar for the cinnamon swirl mixture.

Pour half of the banana batter into the prepared loaf pan. Sprinkle half of the cinnamon mixture on top.

Add the remaining banana batter and top with the rest of the cinnamon mixture.

Lightly swirl the mixtures together using a knife.

Bake for 60-65 minutes, or until a toothpick comes out clean.

Allow the bread to cool before slicing.