Preheat the oven to 350 degrees.
In a large bowl. cream together the butter and both sugars.
Add eggs and vanilla to the butter and sugar mixture. Mix well.
In another bowl, mix together the flour, cornstarch, salt, and baking soda.
Add the dry ingredients to the wet ingredients, and stir until combined. Add chocolate chips.
Line a baking sheet with parchment paper or a silicone baking mat. Scoop the cookie dough using a 1/2 tsp mini scoop (or a spoon). Bake at 350 degrees for 6-8 minutes. Allow the cookies to cool on the baking sheet for 5 minutes before transferring to a wire rack.