Asian greens related to bok choy that can be eaten raw or cooked. Some other names that it goes by are tat soy, tat soi, broadbeak mustard, spoon mustard, spinach mustard, and rosette bok choy.
Tatsoi is a very versatile green, equally suited to being served raw or lightly cooked. To make it easy, just use tatsoi anywhere you'd use spinach. The leaves are delicate enough to be eaten raw in a salad, but hold up well when cooked. The most common way to cook it is in a stir fry where it's not only quick and versatile, but practically foolproof. Lightly steam or saute it, wilt the leaves with a warm dressing, or add them to a soup at the end of cooking.
It has rounded leaves shaped like a spoon, which have a soft buttery texture and a slightly sweet flavor, while its long, light and crunchy, celery-like stalks taste a little like cucumber, with a mild bitterness. Leaves and inner stalk are tender. Typical cooking is to stir fry the leaves and the stalks. They also can be pickled.
The easiest way to prepare the tatsoi before cooking is to chop off the base, releasing the individual shoots and leaves, and then gently washing each piece and drying them thoroughly.