AKA eocharis dulcis.Order moo goo gai pan or another vegetable dish from your local Chinese restaurant and you will find small circular discs with a surprising crunch. Water chestnuts are popular in Asian cuisine. Not true chestnuts, they are tubers, or root plants, that grow in slow-moving or still bodies of water throughout Asia. Fresh water chestnuts are available in the United States, but most consumers purchase the frozen variety from Asian groceries for use in homemade stir-fry or dumpling dishes.