Sift confectioners' sugar. Add granulated sugar. Set aside.
In large bowl, mix powdered egg white and water according to package instructions, to make equivalent of one egg white. Add vanilla and corn syrup, and mix well. Gradually add sugar into egg white mixture, combining well. Use your hands to form into a ball.
Generously sprinkle board or table with cornstarch. Knead cornstarch into mixture until it is shaped into a smooth, manageable ball. At this point, you may wrap the mixture tightly in plastic wrap and refrigerate until ready to use (it will last for many weeks).
When ready, shape into skulls, place onto wax paper, and allow to dry thoroughly. Once dried, you may decorate.
Make colored icing by combining confectioners' sugar with small amounts of water and food coloring. Use the icing to paint the skulls. You can also paint the skulls directly with food coloring, but this method tends to bleed.
While wet, sprinkle the icing with colored sugars or other decorations. The skulls are supposed to look colorful and happy - the dead like to be remembered; the sugar reminds us that death can be a sweet thing, just as life. If the skull is in remembrance of a loved one, you can write that person's name across the forehead.
If you're not going to eat the skulls, use sequins for the eyes and decorate with glitter, glue, and ribbons. Remembering the dead should be a warm and happy thing, as it is in Mexico and many other cultures around the world.Servings: 8 to 10