Preheat the oven to 350℉.
Add all of the dry ingredients to a mixing bowl. Whisk to combine. Set aside.
Next, add the cream cheese, butter, and sugar to the bowl of a stand mixer and whip until light and fluffy. About 3 minutes.
Add the egg, vanilla extract, and eggnog to the stand mixer and whip to combine.
Slowly add the dry ingredients to the wet and mix on medium until a dough has formed. You may need to scrape the sides and bottom of the bowl. The dough should be a little sticky.
Use a 1.5-tablespoon cookie scoop to scoop dough. Place on a cookie sheet and repeat.
Bake for 10-12 minutes.
Once the bottoms are golden brown remove from the cookie sheet immediately and transfer to a cooling rack.
To make the frosting, add all of the ingredients to a large mixing bowl. Using a hand mixer whip until stiff peaks form.
When the cookies have cooled frost them and dust with ground cinnamon.