Swiss chard is a leafy green vegetable that is related to beets and spinach. It has large, dark green leaves with thick, crunchy stalks that can range in color from white to yellow to red. Swiss chard is known for its slightly bitter flavor and is often used in salads, sautés, and soups. It is a nutritious vegetable that is high in vitamins A, C, and K, as well as minerals like magnesium and potassium.