Preheat your oven to 350°F (175°C). Line baking sheets with parchment paper or lightly grease them with non stick cooking spray.
Cream together the butter and granulated sugar until light and fluffy. Add the eggs, eggnog and vanilla extract, and beat until well combined.
In a separate bowl, whisk together flour, baking powder, nutmeg and cinnamon. Gradually add this dry mix to the wet ingredients, stirring until just combined.
Scoop tablespoon-sized balls (or use your trusty cookie scoop) onto prepared baking sheets, spacing them about 2 inches apart.
Bake for 10-12 minutes, or until the edges are just starting to turn golden. Resist the urge to overbake—these cookies are best when soft and chewy!
Cool on the baking sheet for a few minutes before transferring to a wire rack to cool completely.
While your cookies cool, whip up the glaze by beating the cream cheese until smooth. Gradually add powdered sugar and beat until fluffy. Mix in eggnog until you reach a drizzle-worthy consistency.
Finish with a pinch of nutmeg, then drizzle over cooled cookies - if you are storing the cookies for later, consider saving the glaze and adding to the cookies upon plating.