We get them from the Oriental grocery stores -- they’re called “Red Bean Cake” or, more popularly where I grew up, “Hopia Mongo.” They’re round pastries made with flaky layers of paper-thin dough and stuffed with a pasty filling made from finely ground mongo beans.
The hopia is supposed to have originated in China and might have evolved from another bean-based pastry called the Moon Cake, which is a favorite treat for Chinese holidays and festivities. A similar incarnation of the hopia might have originated in Japan, because there’s the cube-shaped mongo bean delicacy we call Hopiang Hapon.
A few days ago, we got our fix of hopia treats from the Chinese store. I’m not sure if the baker intentionally made this bean cake this way, but it sort of freaked me out when I tore off the wrapper. I took these photos with my phone... you tell me what you see.
More about the hopia here: Hopia on Wikipedia