Yield: 1 quart 1 quart whole milk 3 tablespoons starter (plain yogurt with active cultures)     Bring the milk to a boil, then remove from the heat and allow to cool to 115F. Dilute the starter with 1/2 cup of the warm milk in a glass or ceramic bowl,. Stir in the remaining milk and cover securely with cellophane. Wrap the bowl twice with a heavy cloth and set in a warm draft-free area. Let stand for 4-5 hours. Refrigerate the yogurt before serving.