Amaranth has been touted as a miracle grain, a supergrain, and the grain of the future: A dietary staple of the Aztec empire, this ancient crop was "lost" for hundreds of years, and only since the Sixties, following its rediscovery, has it been grown in the U.S.
Amaranth, which has a pronounced earthy sweetness, is not a true grain, which is a nutritional plus: Unlike wheat or barley, amaranth is not deficient in the essential amino acid lysine. These tiny seeds of a weed-like plant are also a very rich source of iron, and supply copper and magnesium. And amaranth is well supplied with dietary fiber. Amaranth can be cooked alone, or combined with grains such as brown rice or buckwheat, and the seeds can be toasted until they pop like popcorn.
The color of amaranth seeds may range from buff to dark purple, but most amaranth sold commercially is pale yellow. Sometimes black seeds (often the seeds of a related plant that grows among cultivated amaranth) are mixed in; they can be very bitter, but since they are so tiny, their flavor will not dominate that of the paler grains.
Harvesting amaranth is a labor-intensive process, so it's a relatively expensive product. Some large supermarkets do stock amaranth alongside rice, barley, and other grains; if you don't find it there, look for amaranth at a health-food store.
Be sure that the package is tightly sealed and clean.
Store amaranth like any grain, in a tightly sealed container at room temperature or in the refrigerator.
The whole seeds, when simmered, produce a thick, oatmeal-like porridge that has a gelatinous texture many find unpalatable. To make amaranth more appetizing, cook a small proportion (up to 15%) of it with another grain (or grains), such as brown rice or buckwheat; follow the cooking instructions for the predominant grain rather than for the amaranth. The seeds can also be baked or steamed. If cooked alone, amaranth benefits from the addition of a strong-flavored cooking liquid, such as beef broth or tomato juice.
Popping: The grains can be toasted as you would sesame or poppy seeds; they pop and puff like popcorn (although much smaller of course). Toast just a tablespoonful of the seeds at a time in a heavy, ungreased skillet, tossing and stirring them over high heat for a few seconds until they pop. One tablespoon will produce about 1/4 cup of popped amaranth.