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

In a small mixing bowl, combine all-purpose flour, light brown sugar, and ground cinnamon for the streusel topping.

Whisk together all-purpose flour, baking soda, salt, and ground cinnamon in a separate bowl.

Mash ripe bananas in a large mixing bowl, then stir in granulated sugar, light brown sugar, melted butter, eggs, and vanilla extract.

Fold the dry ingredient mixture into the wet ingredients until just combined.

Pour half of the batter into the prepared loaf pan, sprinkle with the cinnamon swirl mixture, then top with remaining batter.

Sprinkle the streusel topping over the batter in the loaf pan.

Bake for 50–60 minutes, or until golden brown and a toothpick comes out clean.

Allow the bread to cool in the pan for about 10 minutes before transferring it to a wire rack.