Separate egg yolks from whites. In large bowl, mix yolks with sugar until pale and thick ribbons form when dropped from beaters. Add milk, liquor and nutmeg and combine well. Chill overnight. 

Place beaters and large mixing bowl in refrigerator or freezer. When chilled, add whipping cream and whip until soft peaks form. Set aside. Using a clean bowl and beater, whip the egg whites until soft peaks form. Add whipped cream and egg whites to egg mixture and fold until well incorporated. Sprinkle individual servings with additional nutmeg. 

Note: Egg nog can be stored in pitchers or bowl and refrigerated until use. Since the cream will rise to the top, be sure to stir gently but thoroughly to recombine before serving. The amount of liquor used can be adjusted to taste. Rum, cognac, brandy or bourbon can be used. I use a combination of about 2-1/2 cups dark rum, 1 cup brandy and 1/2 cup bourbon.