All the mustard seeds we offer at L'Epicerie, brown, yellow, and black are either grow in North Dakota or Alberta. Each variety produces a significantly different flavor. The difference between these varieties is more an issue of pungency than flavor. The black and brown seeds, nearly indistinguishable in flavor, are the mildest. The yellow seed has a fresh clean aroma and a pungent biting flavor with substantially more heat. The amount of volatile oil in mustard seed determines the intensity of flavor. Brown mustard seed is becoming very popular in the U.S. Restaurants are using it in European and American dishes. Mustard adds zest to a wide variety of dishes; meat, potato salad, vegetables, and sauces. The seeds are combined with cumin seeds at the beginning of the cooking process and fried in oil until they pop adding a subtle heat and complexity to the dish.