These are Kissaten sponge cakes and there is no doubt Japanese have figured it out a longtime ago and produce some of the best sponge cakes on planet earth. These cakes are foam cakes made with very little (if any) fatty material such as butter, oil or shortening, and which are leavened primarily by the air that is beaten into the egg whites that they contain. Here are a few types that are precisely cut and as you can see, the icing stays perfectly in place.