Mustard is a leafy green vegetable that belongs to the same family as kale, broccoli, and Brussels sprouts. The plant is known for its pungent and spicy flavour, and its leaves are often used in salads, sandwiches, and as a garnish. Mustard greens are a good source of vitamins A, C, and K, as well as calcium and iron. They are also low in calories and high in fibre, making them a nutritious addition to any diet. Mustard seeds can also be used as a spice, and are commonly used to make mustard condiments.