Reduced-sugar recipe with only rice flour replacement was used for the shells. I must admit that these designs are one of the most tedious and challenging to pipe, especially the rainbow. I made these concurrently with the pink unicorn macaron carousels. I have made the rainbow on clouds before so will not mention in detail. Just to share some photos of the process...
Piping unicorn shells
This was on display at the book event at Kinokuniya in April!