If you want to make the best chocolate chip cookies your guests have ever tasted for a delicious Christmas dessert, try these tips: 1. Use real butter. Substituting margarine produces a softer dough which will cause your cookies to go flat. 2. Only buy real vanilla. While it might cost a bit more than imitation, nothing beats its flavor. 3. Melt butter carefully in your microwave at a very low power level. Butter will scorch easily if left unattended at high temperatures. 4. If your brown sugar has hardened into one solid mass, try microwaving that as well. A few seconds is all you'll need to soften it. 5. For variation, try substituting chocolate chips with peanut butter chips, butterscotch morsels, or crumbled heath bar.