In a stand mixer, with the whisk attachment, combine butter, cream cheese, sugars, egg, and vanilla and beat for 5 minutes in a stand mixer or 7 with an electric hand mixer
Scrape the sides of the bowl and slowly add the flour, cornstarch, baking soda, and salt while stirring
Add the chocolate chips and stir slowly with a mixer or fold in by hand
Cover the dough with beeswax wrap or plastic wrap and refrigerate for 30 minutes
Preheat the oven to 350F
Lightly grease a springform pan or baking dish
Spread the dough evenly to the edges of the pan
Bake about 10-15 minutes, until the edges start to brown