This is a traditional delicacy of the Chinese that goes back to hundreds of years. This bird's nest is actually the nest of swiflets, a type of bird. These swiftlets uses their phlegm-like saliva, that hardens once exposed to air, to build nests. Traditionally found in caves, these nests are expensive due to the difficulty in harvesting. It is considered a luxury to many (me included). The better ones (血燕) can cost more than RM1000 per box. Nowadays bird nests are domesticated for harvesting with some even done in buildings in the outskirts.