Heat the oven to 350 degrees F. Spray a 9 x 5 x 3-inch loaf pan with the cooking spray.
Beat the butter and sugar in a medium bowl with an electric mixer on medium speed until the mixture is light and fluffy. Stir in the bananas, salsa and eggs. Stir in the flour and baking soda. Pour the mixture into the loaf pan.
Bake for 1 hour or until a knife inserted near the center comes out clean. Cool in the pan on a wire rack for 15 minutes. Remove from the pan and cool completely on a wire rack.
It's best to set the oven rack in the middle of the oven for this recipe