Preheat oven to 350°F. Grease a bread pan and set aside.
Using either a mixer or hand mixer, mix the butter, sugar and brown sugar together until combined. Add the eggs and vanilla. Mix until combined. Add mashed bananas and stir in gently until mixed.
In a separate bowl, combined flour, salt, baking powder, baking soda, and cinnamon.
Add dry ingredients to the wet ingredients and mix until evenly combined. Don't overmix.
Add a third of the batter to the pan and sprinkle a third of the cinnamon sugar on top. Repeat all three layers. Top bread with cinnamon sugar before baking.
Bake for 55- 65 minutes. Cover banana bread with foil for the last 15 minutes if banana bread becomes too dark.
Remove and let cool in the pan for ten minutes before transferring to a cooling rack.
Banana bread can be kept at room temperature for up to 5 days.