Also called Suukgat, this green leafy vegetable is very popular in Korea as well as China and Japan. They often use it in Udon soups and noodle dishes as well as pancakes. It may be a little bitter the first time you try it so for first time NutriBlasters, this may be something to work toward.
Look at your local Asian grocer for this leafy green. Fresh leaves should not be wilted nor torn. Avoid leaves that are turning brown.