Makes: 12 large and 12 smaller baubles. Prep: 30 minutes. Bake: at 400 degrees for 10 to 12 minutes.
1. Heat oven to 400 degrees F. Grease 2 cookie sheets. On floured work surface, roll out dough to 1/4-inch thickness. Cut out circles, using 3 1/2-inch and 3-inch cutters. Transfer to cookie sheets. Using skewer, make small hole through dough about 1/2 inch from edge.
2. Bake in 400 degrees F oven for 10 to 12 minutes, until cookies darken around edges. Immediately re-shape holes since they may have shrunk during baking. Transfer cookies to wire rack; let cool.
3. Trace bauble templates onto sheet of paper; cut out.
4. Set a quarter of icing aside. Divide remaining icing among 3 small bowls. Tint one red, one blue and one green. Thin each batch with a few drops of water until consistency of thick heavy cream. Cover with plastic wrap or waxed paper pressed onto icing.
5. Arrange cookies in single layer on wire rack; place tray or sheet of parchment paper underneath. Position large bauble template on one large cookie. Add a small amount of reserved white icing to piping bag fitted with medium-size writing tip. Pipe line onto cookie around curved edges of template. Repeat for all cookies, using smaller template on small cookies. Pipe circle of icing around holes. Squeeze extra icing back into bowl and cover.
6. Place red icing into another piping bag or plastic-food storage bag with snipped-off tip. Use to flood top and bottom area of each bauble. Ease icing over edges with fine paintbrush to completely coat cookie. Let dry, at least 1 hour.
7. Place blue icing in separate piping bag as above. Flood central areas of each cookie. If necessary, use paintbrush to take blue icing right up to white, iced lines. Let cookies dry overnight.
8. Fill bag with remaining white icing. Onto blue areas, pipe outlines of trees onto half the cookies; pipe star at tip of some. Pipe dots of white icing around trees. Pipe white, holly-shaped outlines in blue area on remaining baubles, with dots for berries. Dry completely.
9. Place green icing in separate piping bag. Fill tree and holly shapes. Ease icing into corners of shapes with paintbrush. Fill berry outlines with dots of red icing. Let cookies dry overnight. Use more white icing to pipe over the initial template lines. Thread baubles with lengths of ribbon for hanging.