Cut the cookie dough in half. Press one half firmly into bottom of greased 8-inch square baking dish. Beat cream cheese, sugar and egg until smooth. Pour over cookie dough. Crumble the remaining cookie dough and drop onto cream cheese mixture. Bake for 35-40 minutes (or until inserted toothpick comes out clean) at 350oF. Refrigerate leftovers (if you have any!).