Banana leaves are large leaves from the banana tree used as wrappers-and subtle flavoring agents-for steamed Asian dishes. They are usually sold frozen in large pieces to be cut into smaller sizes as needed for wrapping.
People in the tropics use these huge leaves to line cooking pits and to wrap everything from pigs to rice. The leaves impart a subtle anise fragrance to food and protect it while it's cooking. Frozen leaves, once thawed, work just fine. Boil the leaves before using them to keep them from cracking. Look for banana leaves among the frozen foods in Asian, Hispanic, or specialty markets.