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 until well combined.
In a large bowl, mix the melted butter, brown sugar, and granulated sugar until smooth and creamy.
Add the eggs one at a time to the butter and sugar mixture, beating well after each addition.
Stir in the vanilla extract until fully incorporated.
Gradually add the dry ingredients to the wet ingredients, mixing until just combined. Do not overmix.
Fold in the semisweet chocolate chips evenly throughout the batter.
Spread the batter evenly into the prepared 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 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 and place on a cutting board.
Cut into 24 equal bars and arrange on a party display tray for serving.