1. Combine egg yolks and milk in a saucepan over medium heat and cook until the mixture coats the spoon.
2. Once thick, let it cool for a few minutes.
3. While the milk mixture cools, beat egg whites until soft peaks form.
4. Then add egg whites to the milk mixture in the saucepan over low heat.
5. Once in the saucepan, add vanilla extract and sweetener, stirring gently to combine.
6. Remove the saucepan from heat, cover, and let the eggnog chill.
7. Garnish eggnog with a cinnamon stick and sprinkle with some nutmeg and/or cinnamon.
