Make candy clay 1 day in advance. Prepare candy clay following recipe directions using White Candy Melts candy. Let set overnight.
Tint candy clay. Divide candy clay into thirds. Use candy colors to tint one third candy clay each blue, yellow and pink.
Knead candy clay until pliable. Roll a 1 in. ball each of blue, yellow and pink candy clay.
Knead balls of candy clay together, blending gently to create a tie dye look.
Use 9 in. fondant roller with pink guide rings to roll out candy clay 1/16 in. thick on cornstarch-dusted surface.
Use third largest (3 1/4 in.) cutter from nesting circles cutter set to cut circle from candy clay.
Make cupcakes. Prepare batter following recipe directions. Divide batter into thirds. Use icing colors to tint one third batter each light rose, light blue and yellow. Use blue batter in disposable decorating bags to pipe first layer into baking cup. Repeat with a layer of yellow batter, then a layer of rose, until cup is 2/3 full with batter. Bake and cool cupcakes.