Japanese sweet potato jelly cakes from Isetan

Got a box of them from one of the Japanese fairs over at Isetan during the weekends. I'm not sure why these things are called sweet potato jelly cakes since they don't resemble jellies in taste nor in appearances in any way. The textures of these things felt like reconstructed steamed sweet potatoes that are chilled. It was as if cooked sweet potatoes were mashed, mixed with something sweet (just sugar maybe) and then packed back into these bricks. Despite finding them a little too sweet for my usual liking, they were quite addictive. There was a nice flavour from the sweet potatoes as well. I guessing that there wasn't much other ingredients that were used to make them.