Back in Europe of the 1700s, people liked to keep warm during the cold winters. A drink developed that mixed warm milk and eggs with Sherry or Brandy to keep the chill at bay. This was served in a noggin - a small, wooden mug. This became nicknamed as 'eggnog'.
During the 1800s this became hugely popular in England, especially at Christmastime. This was a classic punch served in large volumes to all holiday visitors. It was served both warm and cold to anyone who came calling during the winter season.
Most eggnogs are made with raw eggs. If you're worried about raw egg, here's a version that cooks the egg mixture before using it.
6 eggs, large, separated into yolks and whites
1/2 cup sugar
2 cups milk
1 tsp. vanilla
1 cup half and half
1 cup heavy cream
1/4 teaspoon nutmeg, freshly grated
1/4 tsp. salt
4 tbsp. sugar
1/4 cup cream sherry
1/4 cup dark rum
Cook the egg yolks, sugar, vanilla and milk in a double boiler until thickened and light lemon colored. Remove from heat and place in an ice bath, stirring until cold. Add the half and half and heavy cream. Heat the egg whites, salt and sugar over a pot of boiling water, stirring constantly, until 140 F.
Remove and beat with a whisk or mixer until stiff peaks form, fold this "meringue" into the egg/cream mixture. Chill for one hour before serving. Sprinkle with nutmeg before serving.