Low-fat Eggnog

Combine sugar and water in a small saucepan over medium heat, stirring constantly until the sugar dissolves completely, about 3–4 minutes.

Remove the simple syrup from heat and allow it to cool to room temperature, about 5 minutes.

Place egg whites and cream of tartar in a clean, dry bowl and whisk until soft peaks form, approximately 2–3 minutes of vigorous whisking.

Gently fold the cooled simple syrup into the whipped egg whites using a spatula, preserving as much volume as possible.

Pour the skim milk into a large pitcher or serving bowl and add the vanilla extract.

Carefully fold the egg white mixture into the milk mixture until fully combined but still light and foamy.

Stir in the brandy or rum (½ to 1 cup, depending on desired strength) until well incorporated.

Pour the eggnog into serving glasses or a punch bowl and grate fresh nutmeg over the top of each serving.