There are variety of Chocolate Chip cookie recipes. I always use the Lindt Piccoli Swiss Premium Couverture dark chocolate because of its distinct creamy and luscious taste. Overall, this cookie is moist and chewy at the same time.
One thing I have learned in making cookies is to keep the dough for at least 30 minutes in the refrigerator before baking. This will prevent the cookies from spreading during baking.
I also find that cookies are evenly baked when done one batch at a time. As a rule of thumb, avoid baking multiple trays at the same time.