• With the paddle attachment, whip the softened butter and white and brown sugar until light and fluffy.
• Add the baking powder, cinnamon, and nutmeg. Mix an additional minute or until well blended.
• In a separate medium-sized bowl, mix the eggnog, eggs, and vanilla until well combined.
• With the stand mixer running on low, add the eggnog mixture to the butter-sugar mixture in a stream. Don't worry if the mixture is a bit lumpy.
• Once all the egg mixture has been added, turn the machine off and add half the flour mixture. Mix for a minute or two until well blended. Add the remaining flour and mix until just combined.
• Take the dough from the bowl and put it on top of a large piece of plastic wrap. Wrap the dough in the plastic wrap, forming it into a large rectangle about 1-inch thick. Refrigerate for at least 2 hours or overnight.
• Form the dough into 1-inch balls and bake them on a parchment paper lined sheet pan in a 325-F oven for about 12-15 minutes or until they are lightly golden brown on the bottom.
• Transfer to a cooling rack and when cool, drizzle with the glaze.fc

To make the glaze:

• With the whisk attachment of your stand mixer, combine the powdered sugar with eggnog and spiced rum until smooth and just runny enough that it fall slowly in a stream off of a spoon.
• If the glaze is too thick, add 1 teaspoon of milk or water at a time until the glaze is runny but not watery.