“Alcohol is optional, but for many eggnog lovers, it just isn't as festive without a wallop of rum, brandy, Cognac, or whiskey. Your choice may hinge on personal taste, family tradition, or regional preferences. "I almost always make my eggnog with at least two spirits, such as bourbon and Cognac,” says John deBary, author of Drink What You Want and Saved by the Bellini. Why add more than one liquor to the elixir? “I love the added complexity and the eggs are a great base to hold all the competing flavors from the spirits," he says.”