The main ingredient in mustard is mustard seeds. Mustard seeds are small, round seeds that come from different varieties of mustard plants, including white, brown, and black mustard. These seeds can be ground into a powder or crushed to release their flavor, which is characterized by a sharp, tangy taste. When mixed with liquid, such as vinegar or water, the seeds create the condiment known as mustard, commonly used in sandwiches, dressings, and marinades. Mustard is valued not only for its flavor but also for its culinary versatility and potential health benefits.