Preheat the oven to 350°F (175°C). Grease a 9×13-inch baking pan or line it with parchment paper, leaving an overhang for easy removal.
In a medium bowl, whisk together the all-purpose flour, baking soda, and salt. Set aside.
In a large bowl, combine the melted unsalted butter, light brown sugar, and granulated sugar. Stir until smooth and well combined.
Add the egg, egg yolks, and pure vanilla extract to the butter and sugar mixture. Whisk until fully incorporated and smooth.
Gradually add the dry ingredients to the wet ingredients, stirring gently with a spatula until just combined. Do not overmix.
Fold in the semisweet chocolate chips evenly throughout the dough.
Spread the dough evenly into the prepared 9×13-inch baking pan, smoothing the top with a spatula.
Bake in the preheated oven for 22 to 25 minutes, or until the edges are golden brown and a toothpick inserted into the center comes out with a few moist crumbs.
Remove the pan from the oven and allow the cookie bars to cool completely in the pan on a wire rack.
Once cooled, use the parchment paper overhang to lift the cookie bars out of the pan. Cut into 16 bars and serve.