01 - Preheat oven to 350°F. Grease a 9x5-inch loaf pan and line with parchment paper for easy removal.
02 - In a large bowl, whisk together the flour, baking soda, salt, and cinnamon until well blended.
03 - In another bowl, whisk melted butter with granulated and brown sugar until smooth. Beat in eggs one at a time, then mix in vanilla, mashed bananas, and sour cream until combined.
04 - Add dry ingredients to wet ingredients and gently fold with a spatula until just combined. Do not overmix.
05 - Fold in chocolate chips and nuts, reserving a few chocolate chips for topping.
06 - Pour batter into prepared pan. Sprinkle reserved chocolate chips on top. Bake for 50-60 minutes until a toothpick inserted in the center comes out with a few moist crumbs.
07 - Cool in pan for 10 minutes, then transfer to a wire rack to cool completely before slicing.