One day in advance: Make cookies. Prepare cookie dough and roll out 1/8 in. thick. Cut five small eggs using egg cutter from 18-piece set. Bake and cool.
Prepare Color Flow icing. Tint portions violet, rose, green, blue and yellow.
For egg cookies, use tip 3 and full-strength Color Flow icing to outline cookies. Use a cut parchment bag and thinned Color Flow icing to fill in cookies. Let set. Attach lollipop sticks to backs of cookies with full-strength Color Flow icing. Set aside.
Individually prepare three boxes white cake mix following package instructions. Divide in thirds. In one portion of batter, gently stir in violet icing color to desired shade. (Use clean toothpicks to transfer color from jar to batter.) Repeat with rose icing color for second portion and yellow icing color in third portion.
For bottom layer, place Batter Dividing Ring in the first prepared pan. Pour yellow-colored batter in outer section, rose-colored batter in middle section and violet-colored batter in center. Fill sections 2/3 full. Remove ring from pan by carefully lifting straight up on handles. Rinse and completely dry ring.
For top layer, place clean ring in second prepared pan. Pour violet-colored batter in outer section, yellow-colored batter in middle section and rose-colored batter in center. Fill sections 2/3 full. Remove ring from pan by carefully lifting straight up on handles. Rinse and completely dry ring.
For middle layer, place clean ring in third prepared pan. Pour rose-colored batter in outer section, violet-colored batter in middle section and yellow-colored batter in center. Fill sections 2/3 full. Remove ring from pan by carefully lifting straight up on handles.
Individually bake and cool cakes following recipe directions. Prepare buttercream icing. Tint portions blue and green. Stack and position cake on foil-wrapped cake circle. Ice cake smooth with blue buttercream icing and spatula.
Divide cake into eights with cake dividing chart. Impress large egg cookies on sides of cake at division points. Outline with tip 3 and pipe-in desired egg design.
Use tip 233 and green buttercream icing to pipe pull-out grass bottom border and to pipe pull-outgrass on top of cake. Insert small cookies on cake top.
The star tip creates the most popular, easily accomplished decorations! The serrated edges of the star tip makes ridges in the icing as you squeeze it out. Use for borders, details such as buttons and facial features, flower centers, filling in cakes baked in shaped pans.