1. Preheat oven to 350°F. Combine 18 cookies together.
2. Shape dough into 3 (1/4-cup) balls. Shape remaining dough into 3 more (1 Tbsp) balls.
3. Place the 6 dough balls on ungreased cookie sheet. Bake 10-12 minutes, or until lightly golden.
4. Continue repeating steps, making 3 more balls of each of the following sizes: ¾ Tbsp, ½ Tbsp, 1 tsp and ½ tsp. Reduce baking time of each cookie size, as cookies get smaller.
5. Assemble trees by placing the largest cookies on a serving platter with dab of icing.
6. Drizzle icing around outer edge of cookies to decorate.
7. Place a large dab of icing in center of each cookie. Add next largest cookie and repeat steps, stacking largest to smallest. Add additional icing and decorations, if desired.
8. Serve cookies individually by separating layers with a knife.