The leaves of the brown, leaf, or Indian mustard plant are native to Europe and Asia and have been introduced to the United States, where they now grow as a wild weed. The seeds of this plant are ground to produce the popular condiment mustard, while the dark and robust-tasting leaves are widely used in the culinary traditions of the American Deep South, particularly in Soul Food enjoyed by African Americans. Mustard greens can be prepared similarly to collard greens, which are typically flavored with fat back and slow-cooked for extended periods of time.