Cream together butter and sugars until smooth. Add egg and vanilla and blend in.
Add the flour, corn starch, baking soda and salt and mix until just combined. Stir in the chocolate chips.
Grease or line a baking sheet with parchment. Drop the dough, using tablespoons, about 2 inches apart onto the sheet and bake for about 8-10 minutes. They should be barely golden brown around the edges and still somewhat soft in the center.
Allow the cookies to cool on the baking sheet for 5 minutes before transferring to a rack to cool completely. Or do as I did and just transfer them straight to your mouth while still warm. :)
Recipe by My Little Gourmet at http://mylittlegourmet.com/desserts/chocolate-chip-cookies/