Preheat the oven to 350°. Remove the wrappers from the candies and keep in the refrigerator until ready to use.
For the cookie dough:
Beat butter, sugar, vanilla, and egg in a large bowl until well blended. Stir together flour, baking soda and salt; add alternately with milk to butter mixture, beating until well blended.
For assembly:
Shape dough into 1 inch balls. Roll in red and/or green colored sugar. Place on ungreased cookie sheet.
Bake 8-10 minutes or until edges are lightly browned and cookies are set. Remove from oven; cool 15 minutes. (If you add the kisses too soon they will melt) Press candy piece into the center of each cookie. Remove them from the cookie sheet and cool completely on a wire rack.