Red onions are medium to large onions with deep purple or reddish outer skin and crisp white flesh layered with purple rings. They have a sharp, pungent flavor when raw, often with a slightly sweet and peppery quality. Their crisp texture and vibrant color make them especially popular in salads, sandwiches, salsas, and pickled preparations. When cooked, red onions become softer and sweeter, although prolonged cooking can cause their purple color to fade. They can be sautéed, roasted, grilled, caramelized, or used raw depending on the desired flavor and texture.