WHISK yolks and sugar together in medium, heavy-duty saucepan. Stir in evaporated milk, cinnamon, nutmeg and cloves. Cook over low heat for 15 to 20 minutes, stirring constantly, until mixture reaches 160º F. (do not boil) and is thick enough to coat a metal spoon with a thin film. Remove from heat.
COVER; refrigerate until thoroughly chilled, at least 3 hours or overnight. Remove cloves; discard. Stir in rum. Using a funnel, pour mixture into glass bottle with cap. Keep refrigerated for up to 7 days.
NOTE: Recipe can easily be doubled. More spices can be added to taste. If you like it sweeter, add more sugar.