2Combine flour, baking powder, cinnamon, and nutmeg. Mix well with a wire whisk and set aside.
3Cream sugar and butter until it forms a grainy paste. Stir in eggnog, vanilla, and egg yolks. Beat at medium speed until smooth. Add flour mixture and beat at low speed just until combined.
4Drop cookie dough by rounded teaspoonfuls onto ungreased baking sheets, 1 inch apart. Sprinkle lightly with nutmeg. Bake for 20 to 25 minutes, or until bottoms turn light brown.