Mustard greens are leafy greens with a slightly bitter flavor, part of the mustard family that includes cabbage, broccoli, and cauliflower. They are a good source of vitamins, especially vitamin K, and minerals like calcium and iron. One of the many ways to cook mustard greens is to saut them in a skillet with other vegetables or meat.
Mustard greens have been cultivated for centuries in China and Japan, and were brought to the United States by European colonists in the 18th century. They are now grown all over the world and are a popular ingredient in many cuisines.