Combine milk with spices and sugar in large heavy
saucepan. Cook over medium heat, stirring to dissolve sugar, until milk
just starts to bubble around the edges (scalding). Lower heat and cook 10
minutes. Remove from heat and allow to steep 10 additional minutes, then
strain into another large heavy pot. Heat gently, then add chocolate and
rum. Whisk briskly 5 minutes over low flame until chocolate is completely
melted.