Preheat oven to 350 degrees Fahrenheit. Grease a 1lb (8×4-inch) bread pan with cooking spray. Set aside.

In a large bowl, mash bananas thoroughly with a fork or potato masher, until smooth. Add the melted butter, sugar, egg, and vanilla. Mix until combined well.

Add the flour, baking soda, and salt. Stir the dry ingredients slightly before folding into the wet batter. Mix until flour barely disappears.

In a separate small bowl, mix together the cinnamon and sugar for the swirl and topping.

Spread half of the batter into the bottom of the prepared loaf pan. Sprinkle all but 2 Tablespoons of the cinnamon-sugar evenly over the batter.

Dollop, then spread the remaining batter over the cinnamon sugar. (NOTE: The cinnamon-sugar may stick and pull-up with the batter as you spread. Just be careful.) Top with the remaining 2 Tablespoons of cinnamon-sugar. Use a knife to swirl the batter. (I swirled up-and-down a few times one way, then left-to-right a few times the other way, using the full length of the pan in both directions. Then stopped. I also didn’t dip my knife in very far, so the middle layer would remain as one thick stripe.)

Bake at 350˚F for 50-60 minutes, or until a toothpick comes out clean from the center. Be extra observant because the batter may scrape off with the cinnamon-sugar crust on top.

Allow bread to cool in pan for 5-10 minutes before inverting: then cool completely on a wire cooling rack. Slice with a serrated knife and serve.