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