01 - Preheat oven to 350°F. Grease and flour a 9x5-inch loaf pan or line with parchment paper.
02 - In a large bowl, mash bananas until smooth. Stir in melted butter until combined, then whisk in eggs, granulated sugar, brown sugar, and vanilla extract until smooth and well blended.
03 - In a separate bowl, whisk together flour, baking soda, salt, and ground cinnamon until evenly distributed.
04 - Gently fold dry ingredients into wet mixture until just combined. Do not overmix. Fold in nuts or chocolate chips if desired.
05 - Pour batter into prepared loaf pan and smooth top. Bake for 50-60 minutes until a toothpick inserted into center comes out clean or with a few moist crumbs.
06 - Allow bread to cool in pan for 10 minutes, then transfer to wire rack to cool completely before slicing.