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 flour, baking soda, salt, and cinnamon until well blended.
03 - In another bowl, whisk melted butter, granulated sugar, and brown sugar until smooth and combined.
04 - Beat in eggs one at a time. Mix in vanilla extract, mashed bananas, and sour cream or Greek yogurt until fully incorporated.
05 - Gently fold dry ingredients into wet mixture using a spatula until just combined. Avoid overmixing to prevent tough texture.
06 - Fold in chocolate chips and nuts, reserving a few chocolate chips for topping if desired.
07 - Transfer batter to prepared loaf pan. Sprinkle reserved chocolate chips across the top.
08 - Bake for 50-60 minutes until a toothpick inserted into the center comes out with just a few moist crumbs.
09 - Cool in pan for 10 minutes, then transfer to wire rack. Cool completely before slicing for best results.