Preheat the oven to 350°F (175°C) and position the rack in the middle.

Use an 8X8 baking pan lined with parchment paper and lightly spray with nonstick cooking spray.

In a mixing bowl, combine melted butter and granulated sugar. Beat with a hand mixer on medium speed for 2–3 minutes until smooth and slightly fluffy.

Add in the vanilla and egg and continue to beat on low speed until combined.

Gradually add the flour and mix gently until fully incorporated, avoid overmixing.

Fold in the chocolate chips using a spatula until evenly distributed throughout the batter.

Transfer the batter into the baking pan and smooth the surface evenly.

Bake for 20-25 minutes, or until the edges are golden brown and a toothpick inserted into the center comes out with some moist crumbs.

Remove the blondies from the oven and let it cool in the baking pan for about 15 minutes.

Cut into desired portion size and store in an airtight container at room temperature for up to 5 days.