Separate the eggs. Whisk the egg yolks to a light, foamy mass in a mixing bowl. Add the sugar and continue whisking until fluffy. In a separate bowl, whisk the egg whites and
Gently heat the milk, cinnamon and cloves in a saucepan, but do not boil. Stir half of the milk into the egg yolk mixture to even out their temperatures, then return the egg and milk mixture to the saucepan. Reheat over low to medium heat until the mixture thickens, stirring continuously with a wooden spoon. Do not allow to boil!
Remove the pot from the heat and stir in the cream. Remove the cinnamon stick and cloves and leave the eggnog to cool. Season with nutmeg, allspice and vanilla extract to taste and add the rum and whiskey. Gently fold in the whisked egg whites and refrigerate the eggnog for at least 1 hour. Transfer to glasses and serve garnished with ground cinnamon.