Named for its pearlike shape and size, this fruit comes from any of several varieties of cactus. Its prickly skin can range in color from green to purplish-red; its soft, porous flesh (scattered with black seeds) from light yellow-green to deep golden. Also called cactus pear, the prickly pear has a melonlike aroma and a sweet but rather bland flavor. It's extremely popular in Mexico, Central and South America, the Mediterranean countries and southern Africa, and is slowly gaining favor in the United States. Prickly pears are available in Mexican markets and some specialty produce markets from fall through spring. Choose fruit that gives slightly to palm pressure. It should have a deep, even color. Ripen firm prickly pears at room temperature until soft. Store ripe fruit in the refrigerator for up to a week. Prickly pears are usually served cold, peeled and sectioned with the seeds removed.