Preheat your oven to 400°F (205°C).

In a large mixing bowl, combine cold, cubed butter with granulated and brown sugars. Beat with an electric mixer on medium speed for about 4 minutes until light and fluffy.

Add the eggs one at a time along with the pure vanilla extract. Mix for an additional minute, scraping down the sides of the bowl.

In a separate bowl, whisk together the all-purpose flour, cornstarch, baking soda, and salt. Gradually incorporate this dry mixture into the wet ingredients.

Fold in the chocolate chips gently to ensure even distribution.

Optionally, wrap the dough in plastic wrap and chill for at least 30 minutes to enhance flavor and chewiness.

Line your baking sheets with parchment paper. Scoop out the dough, placing each scoop at least 2 inches apart.

Bake the cookies for 8 to 11 minutes until edges are golden brown and centers are slightly soft.

Cool on the baking sheet for about 5 minutes before transferring to a wire rack.