Beat the yolks separately and add 1/2 cup sugar while beating. Beat until sugar is dissolved and mixture is thick; set aside.
Beat the egg whites separately and add 1/4 cup sugar after they have been beaten very stiff. Mix the egg yolks and egg whites together. Stir in the heavy cream and whole milk. Then add brandy (or whiskey) and the ounce of rum. Stir thoroughly and serve very cold with grated nutmeg on top of each glass.