1. In a large bowl, cream together the softened butter and granulated sugar until fluffy and pale.

2. Add the egg yolk, vanilla extract, and 2 tablespoons of eggnog. Beat until fully combined.

3. In another bowl, whisk together the flour, salt, and nutmeg.

4. Gradually add the dry ingredients to the wet, mixing until a soft dough forms.

5. Divide dough in half, flatten into discs, wrap in plastic wrap, and chill for at least 1 hour.

6. Preheat oven to 350°F (175°C). Roll out dough on a floured surface to 1/4-inch thickness.

7. Cut into star shapes or other festive cookie cutters and place on parchment-lined baking sheets.

8. Bake for 9–11 minutes, until edges are lightly golden. Cool 5 minutes on sheet, then transfer to wire rack.

9. To make the glaze, whisk 1 1/2 cups powdered sugar with 3 tablespoons eggnog until smooth and spreadable.

10. Once cookies are fully cooled, glaze each cookie.

11. Dust lightly with cinnamon or cocoa if desired and top with sprinkles.

12. Let glaze set 15–20 minutes before serving or storing.