Draw a template on parchment paper (see below) and place another piece of parchment over the template so you can make a few faces with icing or candy melts until you get the look desired.
The icing is very fragile when dried, so you'll want to make them thick and let them dry completely, usually overnight. I placed a small fan on mine, overnight. If using candy melts, place in fridge to firm up. When completely dry, gently peel parchment back to release the face pieces, but be very careful, they will break if you move peel too quickly.
After your face pieces are ready, cut the half moon shape out of your template and place the non-face side of your template on the cheesecake. Sprinkle black sugar crystals to the exposed cheesecake to create a dark side of the moon. Carefully remove the parchment template to reveal the black sugar half moon.
Place your pieces onto your cheesecake to transform this basic cheesecake into a Halloweenready piece of art! Happy Halloween!