Preheat your oven to 350°F (175°C) and grease a 9x5-inch loaf pan.
In a large bowl, combine the mashed bananas and melted butter, stirring until well mixed.
Add the sugar and beaten egg to the banana mixture, mixing until fully incorporated.
Stir in the vanilla extract, baking soda, and salt, ensuring everything is evenly combined.
Gradually add the flour, mixing until just incorporated — be careful not to overmix.
Fold in the chocolate chips and chopped walnuts (if using) until evenly distributed throughout the batter.
Pour the batter into the prepared loaf pan, smoothing the top with a spatula.
Bake in the preheated oven for 50-60 minutes, or until a toothpick inserted into the center comes out clean.
Allow the banana bread to cool in the pan for 10 minutes, then transfer it to a wire rack to cool completely.
Notes
Slice the banana bread and serve it warm or at room temperature. For an extra touch, drizzle melted chocolate over the top or serve with a dollop of whipped cream!