Roll out cookie dough about 1/8 in. thick; cut 1 round cookie using 2nd largest circle cutter. Bake 8-11 minutes or until edges start turning light brown. Cool on cooling grid. While cookie is still warm, transfer Yin/Yang pattern Need a link to this pattern onto cookie top with toothpick. Using full strength royal icing and tip 2, outline cookie and center circles in corresponding colors. Flow in thinned icing with a cut parchment bag. Set aside to dry overnight. When dry, attach cookie stick to cookie with full strength royal icing, leaving 3" of stick exposed. Let dry.
Bake your favorite 2-layer cake recipe or mix in 8 in. square pan. Cool cake in pan on cooling grid 10 minutes. Remove from pan and cool completely. Wrap cake board with Fanci-Foil. Arrange cake on prepared cake board.
Ice cake smooth with white buttercream. Attach triangles with no slits onto cake sides in an overlapping pattern, using dots of icing if needed. Pipe tip 18 shell top and bottom border. Insert cookie into top of cake. Assemble remaining triangles and position on cake top and on cake board around cake.