Preparation: Preheat your oven to 350°F (175°C). Grease or line an 8x8-inch baking pan with parchment paper, leaving an overhang for easy removal.
Combine Wet Ingredients: In a large mixing bowl, whisk together the melted butter, brown sugar, and granulated sugar until well combined and smooth.
Add Egg and Vanilla: Add the egg and vanilla extract, whisking until fully incorporated.
Mix Dry Ingredients: In a separate bowl, sift together the flour, baking soda, and salt. Gradually add the dry ingredients to the wet ingredients, stirring until just combined.
Add Chocolate Chips: Fold in the chocolate chips until evenly distributed throughout the batter.
Spread Batter: Spread the batter evenly into the prepared 8x8-inch baking pan, using a spatula to smooth the top.
Bake: Place the pan in the preheated oven and bake for about 20-25 minutes or until the top is golden brown and a toothpick inserted into the center comes out clean or with a few moist crumbs.
Cool and Slice: Once done, remove the pan from the oven and allow the cookie bars to cool completely in the pan on a wire rack. Once cooled, lift the bars out of the pan using the parchment paper overhang and slice them into squares or bars.
