Begin by preheating your oven to 350°F (175°C). Prepare an 8x8 inch baking dish by greasing it lightly or lining it with parchment paper.
In a large mixing bowl, add the melted butter and the mashed bananas. Blend them together with a fork or a whisk until smooth.
Incorporate the brown sugar into the banana mixture, stirring until fully integrated. Then, add the egg and vanilla extract, mixing until uniformly combined.
In a separate bowl, sift together the all-purpose flour, baking soda, and salt.
Gradually fold the dry ingredients into the wet mixture using a spatula, stirring gently just until combined.
Carefully fold in the chopped walnuts and chocolate chips, ensuring they are evenly distributed throughout the batter.
Pour the prepared batter into the greased baking dish, using a spatula to spread it out evenly.
Bake the blondies in the preheated oven for 25-30 minutes, until a toothpick inserted in the center comes out clean or with a few moist crumbs attached.
Remove the blondies from the oven and let them cool in the pan for approximately 15 minutes before transferring to a wire rack to cool completely.
Once cooled, use a sharp knife to cut the blondies into squares. Serve and enjoy!
Notes
Serve on a vibrant plate and dust with powdered sugar for an elegant touch.