Chinese celery, also called Leaf celery, is a variety of celery cultivated in East Asian countries for its edible, flavorful stalks and leaves. The stems are thinner than those of Western celery, and curved into round, hollow stalks. Also, unlike with Western celery, the leaves are used as well as the stalks. It's most customarily used in soups or sauces, but really can be used in anything. It tastes almost like a cross between celery and parsley.
Want to learn more? Look up Chinese Celery on Wikipedia.
STORE: In a plastic bag in the crisper drawer