Preheat oven to 350°F and grease a loaf pan.
[optional: heat butter in a light colored pan until golden and nutty. Set aside and cool until room temperature/softened]
In a bowl, cream together both sugars and softened butter.
In the same bowl, add in eggs, mashed bananas, sour cream, and vanilla. Mix until combined.
In separate bowl, mix flour, baking soda, salt and cinnamon.
Slowly add the dry ingredients into the wet ingredients just until combined. Do not over mix—use a silicone spatula and fold together.
[Optional: Add in ½ cup of nuts, chocolate chips, etc.]
Bake at 350 for 45-55 minutes or until a toothpick comes out clean in the middle.
Let cool for 10 minutes in the pan, then rest on wire rack for 20 minutes.
Use bread knife to cut 1” slices and don’t eat the whole thing by yourself!!