Watercress is a cruciferous vegetable that belongs to the mustard family. Its leaves and stems have a peppery flavor. This makes it a suitable aid when you have to spice up soups, casseroles and salads. It also makes a great addition to most sandwich fillings. The bright green vegetable can also be consumed in juice form or used as a garnish. It is widely recognized as a super-vegetable due to its rich vitamin and mineral content.