In the mixing bowl of a stand mixer, mix the Powdered sugar, Milk, and Vanilla on low speed until blended, then mix on higher speed until mixed completely.
Divide the Frosting evenly, into three individual dishes or Ramekins, add a few drops of food coloring to the Frosting, and stir well until desired color is reached.
Add colored Frosting to clear piping bags, and snip off the tip of each bag, leaving a small opening at the tip of the bag.
Pipe the Black Frosting in the opening for the eyes and mouth.
Sprinkle the Black Sugars on top of the Frosting, and with a small brush, brush away any excess sugars.
Pipe the Orange Frosting around the edges of the cookies, then fill in each cookie with the Orange, all but the cut outs for the eyes and mouth
Pipe the Green Frosting onto the stem of the cookies, and Sprinkle with Halloween Sprinkles on the stem.
Pipe thin lines of Orange Frosting down the Cookie to mimic pumpkin spines
Serve and Enjoy!