Roll out, cut and bake the sugar cookies.
While cookies are cooling, mix the buttercream frosting. Tint about one cup of the frosting with 2 drops Burgundy and 1 drop Super Red gel paste food coloring (this creates a cranberry shade of red). Cover with plastic wrap and set aside. Tint about one-third of the remaining frosting with 3-4 drops of the leaf green gel paste (add more for a darker color). Reserve about two-thirds of the frosting without tinting.
Prepare the piping bags: Fit two, 12-inch piping bags each with an Ateco 7 round tip. Fill one bag, half full, with green frosting. Fill the other bag, half full, with white frosting. Place all of the red frosting in one bag and make a small cut at the tip of the bag. Keep bowls with extra frosting covered with plastic wrap until ready to refill bags.
Option 1: Christmas tree with snow
Start with the cookie upside down - it's easier to create the layered look this way.
At the bottom of the cookie, create a zig zag pattern that follows that row of the cookie cut out.
On the next row, repeat that same zig zag pattern, but slightly overlap it with the first row.
Continue this pattern, row by row until the entire Christmas tree cookie is frosted. Before the frosting dries, you'll need to add the sprinkles.
Place the white nonpareils on a small plate. Gently dip the frosted tree in the sprinkles, frosting side down. Only allow the raised parts of the frosting to barely touch the sprinkles - this gives it a snow-kissed look.
Option 2: Christmas tree with red dots
Repeat the same zig zag pattern as you did for the Christmas tree with snow.
Squeeze several dots of the cranberry frosting in various places on the Christmas tree cookie. Release the frosting in one spot, squeeze and release as you lift up. The idea is to make it look random and not too perfect. These could look like berries, flowers or ornaments...however you imagine!
Option 3: The round cookie with the holly and berries
Using the white frosting, pipe an outline of a circle around the diameter of the round cookie. Go back in and fill the center of the circle with more frosting. No need to make this look perfect - you're going to smooth it out next.
Dip the icing spatula in the warm water and tap it a couple of times on the side of the glass. Gently smooth out the white frosting, creating a flat surface. The warm water slightly melts the frosting, making it easier to smooth out.
Using the green frosting, make a crescent shape on the left hand side of the cookie. Create several "branches" along the crescent.
Using the red frosting, place several small dots in and out of the branches. This creates the cutest holly and berries look!
Option 4: White star with gold sprinkles
Similar to Option 3, first pipe an outline of the star on top of the cookie. Fill it in with white frosting.
Dip the icing spatula in warm water and smooth it out creating a flat surface.
Gently dip one side of the star in the sprinkles, frosting side down. Only allow about one-third of the cookie to get coated in sprinkles. Again, we're not going for a perfect look here - the more random looking the better!
See Notes for make ahead and storing options.
Enjoy!