I found this picture on the supercook website: www.supercook.co.uk so I suppose you really should use their icing…  Simple enough for children to make themselves - leaving you time to sit back and wonder what sort of mess they’ll leave your kitchen in….

 Buy some undecorated cakes (or make your own) and ice them - then pop two halves of a white chocolate drop (with hundreds of thousands) into the top and using writing icing draw in the body and face. The clever person who made the one in the photo also used sweets to create antenna which looks lovely but who has a party full of children who’d appreciate such fiddly effort…?