Eggnog

Combine milk, cloves, cinnamon and the first portion of vanilla in a large saucepan. Heat on low for five minutes. Slowly bring to a boil.
In a large bowl, combine egg yolks and sugar. Whisk together until fluffy.
Slow whisk the hot milk mixture into the egg yolks, a little at a time.
Pour back into the saucepan and cook over medium heat, stirring constantly, for about 3 minutes, or until thick. Be careful not to let it boil.
Strain into a large pitcher, cover and let cool for about an hour.
Stir in the cream, nutmeg, and second portion of vanilla. Stir in rum, if desired.
Refrigerate overnight before serving.