My personal eggnog recipe is quick and easy:

1. Break two medium eggs in a bowl and whisk till blended.
2. Add one package of vanilla sugar, and 1 cup (1/4 liter) milk and whisk until the sugar dissolves.
3. Add fresh ground nutmeg to taste.

Best serve chilled. If you want warm eggnog, warm the milk before you add it to the eggs (heating the mixture may just result in scrambled eggs floating in milk).