Carefully separate the egg yolks from the whites, placing yolks in a large mixing bowl and setting whites aside in a separate bowl.

Beat the egg yolks and sugar together using an electric mixer or whisk until smooth, pale yellow, and slightly thickened, about 2 to 3 minutes.

Slowly add the milk, heavy cream, and ground nutmeg to the yolk mixture while continuing to beat until everything combines into a silky-smooth base.

At this point, you can serve the eggnog as is for a traditional rich version and save the egg whites for another use, or continue to the next step for a lighter, fluffier texture.

Optional: Beat the reserved egg whites with an electric mixer until they form stiff, glossy peaks that stand straight up without drooping.

Optional: Gently fold the beaten egg whites into the eggnog mixture using a spatula with an under-and-over motion, being careful not to deflate the air bubbles.

To serve, place a few ice cubes in each glass and pour 1 to 2 ounces of alcohol over the ice if using, then ladle the eggnog overtop.

Grate fresh nutmeg directly over each serving and add a cinnamon stick garnish for presentation.

Serve immediately for best texture, or refrigerate for up to 1 hour before serving. Enjoy responsibly.