Add the almond milk, whipping cream, pumpkin pie spice, nutmeg, and cinnamon to a saucepan over medium heat on the stove. Simmer for 10 minutes.

In a mixing bowl, combine the egg yolks and sweetener. Beat until they are fluffy.

Slowly add a little of the heated mixture on the stove to the egg yolk mixture, whisking continuously until it is tempered.

Slowly pour the egg yolk mixture into the saucepan. Whisk thoroughly to combine.

Reduce the heat to medium-low and continue to simmer for another 10 minutes.

Remove from the heat and add the vanilla and rum if desired. Stir to combine.

Place the eggnog in the refrigerator to chill and thicken before serving.