Begin by blooming the unflavored gelatin in a small bowl with cold water, letting it sit for about 5 minutes.

In a medium saucepan, combine eggnog, sugar, vanilla extract, and nutmeg over medium heat. Stir and warm until hot but not boiling, about 5 minutes.

Remove the warm eggnog mixture from heat and whisk in the bloomed gelatin until completely dissolved.

For extra smoothness, strain the mixture through a fine-mesh sieve into a pouring jug or bowl.

Pour the strained mixture into ramekins or silicone molds. Let sit at room temperature for 20 minutes, then refrigerate for at least 4 hours, or overnight.

To unmold, briefly dip the ramekins in warm water for easier release, then invert onto serving plates and dust with nutmeg or serve with whipped cream.