In a bowl, combine the flour, cornstarch, baking soda, and salt; stir to blend thoroughly.
In a mixing bowl with an electric mixer, beat the granulated and brown sugars with the butter until light and fluffy. Add the eggs, one at a time, beating well after each addition. Add the vanilla and beat until blended.
With the mixer on low speed, beat in the flour mixture until the dough is moistened. Fold in the chocolate chips. Cover the bowl and refrigerate for at least 2 hours or overnight.
Preheat the oven to 350 F.
Line baking sheets with parchment paper or grease lightly.
Drop dough by tablespoon or cookie scoop onto the prepared baking sheets, leaving about 2 inches between cookies.
Bake for about 10 minutes. The bottoms should be slightly browned, and the tops will still be soft and look slightly underdone. For crispier cookies, bake for about 12 minutes, or until the tops are well browned.
Remove to racks to cool completely. Store the cooled cookies in airtight containers.
Notes
Nutritional information is based on a third-party application and should be considered an estimate. Values may differ depending on brands, ingredient measurements, and serving variations.