Transfer bowl, sieve, and yogurt to refrigerator; drain 12 hours (
discarding liquid occasionally to make sure liquid collected from yogurt in bowl doesn't touch sieve).
Bring
liquid to a boil and cook,
occasionally spooning off fat from surface, until a thick, syrupy glaze forms, about 10 minutes (there will be about 1 1/2 cups glaze and up to 1 cup fat;
discard fat).