The traditional Christmas drink made with eggs, milk, and sugar is eggnog.
Eggnog is a rich, sweet dairy drink traditionally prepared with milk or cream, sugar, and beaten eggs. Nutmeg or cinnamon is often added, and alcoholic versions may contain rum, brandy, bourbon, or another distilled spirit. It can be served chilled or, in some regional variations, warm.
The drink developed from older European milk- and egg-based beverages. In Britain, wealthy households mixed milk and eggs with wine, sherry, brandy, or other spirits. When the recipe crossed into the British colonies during the 18th century, rum became a practical substitute because imported brandy and wine were heavily taxed.
A common misconception is that eggnog must contain alcohol. Commercial and homemade versions are frequently alcohol-free. Modern products may also use pasteurized eggs, reduced-fat milk, flavorings, stabilizers, or thickeners. Similar drinks exist elsewhere, including Mexico’s rompope and Germany’s advocaat, but “eggnog” is the standard Christmas answer in English-speaking North America.