Mustard greens
These flavorful, spicy greens come form the same plant that makes mustard seed (which is commonly ground to make the popular condiment). Mustard leaves can be flat, crumpled or lacy-edged, and can take on a number of colors.
One of the most pungent and interesting of all the greens, as well as a very generous source of vitamin A, mustard greens are widely used in French, Chinese and Southern U.S. cuisines.