First, carefully separate the eggs, ensuring no yolk gets into the whites. Keep the egg whites refrigerated.
In a bowl, combine the yolks and brown sugar. Gradually add the sugar in small portions while beating the mixture until it becomes a creamy, lemon-yellow color.
Meanwhile, gently heat milk in a saucepan over low heat. Stir in the vanilla essence, clove powder, and half of the nutmeg powder, then bring to a simmer.
Slowly incorporate the yolk mixture into the warm milk, adding it in thirds and mixing thoroughly after each addition.
Turn off the heat and allow the mixture to cool to room temperature. Then, gently fold in the cream, followed by your choice of liquor. (I prefer to add the liquor after setting aside a non-alcoholic portion.)
Strain the mixture and refrigerate for at least an hour.
The egg white is added just before serving. You can store the drink for up to a week without the egg white.
When you're ready to serve, beat the chilled egg whites with castor sugar until you have a light and fluffy meringue.
Now it's time to mix the meringue with the drink gently. Pour this frothy delight into glasses, and for a final touch, sprinkle a little nutmeg powder on top. Serve chilled! For an extra festive look, garnish your Christmas Eggnog with a cinnamon stick.