Combine Dry Ingredients: In a small bowl, whisk together flour, cornstarch, and baking soda. Set aside.
Cream Butter and Sugars: In a large mixing bowl, cream together the butter, granulated sugar, and brown sugar until light and fluffy.
Add Eggs and Vanilla: Mix in the eggs one at a time, beating well after each addition. Then add the vanilla extract and mix until combined.
Add Dry Ingredients: Gradually add the flour mixture to the butter mixture, mixing until fully incorporated. Scrape down the sides of the bowl as needed.
Add Chocolate Chips: Gently fold in the chocolate chips.
Chill the Dough: Cover the dough with plastic wrap and chill for at least one hour, preferably overnight.
Soften Cookie Dough: Remove the dough from the fridge and let it soften for 20-30 minutes to make scooping easier.
Preheat the Oven: Preheat the oven to 325℉ (165℃) and line two baking sheets with parchment paper or silicone baking mats.
Scoop the Dough: Use a 1.5-tablespoon scoop (or a #40 cookie scoop) to portion the dough. Place the scoops 2 inches apart on the prepared baking sheets.
Bake: Bake for 14-16 minutes or until the edges are golden brown. Remove from the oven and let the cookies rest on the baking pan for 5 minutes before transferring to a cooling rack.