Note: Color Flow icing takes 24 hours to dry, so you will want to start your project at least 1 day in advance to serving.
Make cookies. Prepare and roll out dough cookie dough following recipe directions. Use cutters from set to cut one bunny and one flower cookie for each treat. Bake and cool cookies, separately.
Mark pattern when cookies have cooled completely. Use black edible color marker to draw diagonal lines on bunny cookies, 3/8 in. apart, leaving 1/8 in. open at edge of cookie.
Outline cookies after marking pattern. Prepare Color Flow icing following recipe directions. Tint portions light teal, dark teal, light violet and dark violet. Reserve some white icing.
Use tip 3, cut disposable decorating bag and full-strength white icing to outline bunny and tail cookies. Let set, about 1 to 2 hours, and then fill in.
Fill in bunny cookies. Use thinned icing in cut disposable decorating bag to fill in diamond shapes in pattern, working in diagonal rows as follows. Fill in one diamond in dark teal or dark violet. Immediately fill in the next diamond in the row in light teal or light violet. Continue filling in diamonds in each diagonal row in alternating shades. Start each row in the opposite color of the previous row. Let dry 24 hours.
Fill in tail cookies. Use thinned dark teal or dark violet icing in cut disposable decorating bags to fill in cookies. Immediately sprinkle with white sparkling sugar. Also, let dry 24 hours.