I bough a box of these from the Hokkaido fair at Isetan sometime back. Yummy. Hokkaido is famous for milk and dairy products. I remember having lots of yummy soft-cream, milk and cakes in Hokkaido.. but I didn't know they had such good and light cheesecake. I'd keep that in mind the next time I go Hokkaido!
I think the Hokkaido fair was really interesting (albeit really crowded).. They really had quite a lot of rather special food on sale there.
Isetan sometimes organise fairs with special produce coming over from various parts of Japan. Another place that does this is Mediya, at Liang Court.
Hakodate Cheese cake.. also called Maru Cheese.. Maru means round in Japanese..
I'm assuming it's because of the shapes the cakes come in!
Super light cheesecake.. yummy!