Preheat your oven to 350°F (175°C) and grease a 9x5-inch loaf pan.

In a large mixing bowl, mash the bananas until smooth.

Pour in the melted butter and mix until fully incorporated.

Add granulated sugar and eggs, then mix until smooth. Stir in vanilla extract.

In a separate bowl, whisk in flour, baking soda, salt, cinnamon, and nutmeg.

Gradually add dry ingredients to the wet mixture and mix gently until just combined.

If using, fold in chopped walnuts or pecans.

Pour batter into the prepared loaf pan and gently tap on the counter to release air bubbles.

Bake in the preheated oven for 55 to 65 minutes. Check for doneness with a toothpick.

Once done, let it cool in the pan for about 10 minutes before transferring to a wire rack.