In a medium bowl, combine flour, baking soda, baking powder, cornstarch, and salt.

In the bowl of a stand mixer, beat butter, cream cheese and sugars until light and creamy, about 2 minutes.

Add in vanilla and eggs, one at a time, beating well after each addition.

Gradually beat in the dry mixture, then stir in the chocolate chips.

Wrap dough in plastic wrap and refrigerate at least 2 but no more than 72 hours.

When ready to bake, take dough out of fridge to get it to a scoopable consistency. Preheat oven to 350 and line baking sheets with parchment paper.

Divide dough into 2 tablespoon sized balls, and bake 10 minutes or until light golden brown.