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 the bananas until smooth. Stir in melted butter until combined.
03 - Whisk in eggs, granulated sugar, brown sugar, and vanilla extract until smooth and well blended.
04 - In a separate bowl, whisk together flour, baking soda, salt, and cinnamon.
05 - Gently fold dry ingredients into wet mixture until just combined. Do not overmix.
06 - Fold in nuts or chocolate chips if desired.
07 - Pour batter into prepared loaf pan and smooth the top.
08 - Bake for 50-60 minutes, or until a toothpick inserted into center comes out clean or with few moist crumbs.
09 - Allow bread to cool in pan for 10 minutes, then transfer to wire rack to cool completely before slicing.