Preheat oven - 410 degrees If your oven runs hot, I suggest reducing heat to 400 degrees See below in notes for further detail
In a large mixing bowl, cream together the butter, brown sugar, and sugar for 4 minutes, until light and fluffy Scrape the sides of the bowl
Add eggs and vanilla, if using Mix for 1 minute longer
Fold in flour *, cornstarch, baking soda, and salt Mix just until combined - avoid overmixing Fold in chocolate chips
Line a light colored baking sheet with parchment paper Place the cookie dough balls on baking sheet and bake for 9 - 12 minutes or until golden brown on the top See below for tips
Let them rest for at least 10 - 15 minutes to allow time to set up
Store in an air-tight container
