I just got some stuff at the Vietnamese market that's labeled "Banh Chung Dhac Biet" (of course with lots of accent marks that I can't reproduce). The only English is "Rice and Bean" (so I'm assuming those are the only ingredients?). It appears to be wrapped in a banana leaf. What is this stuff? What can I do with it? How should I store it? (It wasn't refrigerated at the store, but I threw it in just to be safe.)