In the States, Amaranth is best known as the holy grain crop of the Andes, where it was the staple grain of the Incas. It was also an important ritual food; cakes of it were made with the blood of sacrifices and this led to it being forbidden by the colonial priests. It's an incredibly productive plant, the large grain varieties can produce over a pound of seed per head.
There are also several ornamental amaranths; "Love lies bleeding" is one of the best known. I'm growing one grain Amaranth - Orange Giant (which I planted way too late so it's not "giant" at all...maybe next year...), and a beautiful deep red one called "Hopi Red Dye," that has seeded itself prolifically each year since I first planted it in my last garden several years ago. It was used as a source of red dye for ceremonial foods. My apologies for the really bad quality of the picture here. The plants are quite puny as well since it's being grown in the dry flower bed, but it goes to show just what a tough plant it is!
But there are local, native Amaranths in Turkey too, and they are just as tough. None of them are showy, they are green plants with green flowers, some with red stems. They are mostly considered weeds here, and will come up in waves wherever the soil is watered regularly and lots of places where it is not.
I would probably be trying to eradicate it entirely if it weren't for the fact that it's one of my all-time-favorite summer greens. Istanbul is not such a center of wild green lore as other parts of Turkey, and many local people just pull it out without ever thinking of eating it, but in the Aegean region, "Sirkemotu" is a very well-known and popular wild green. It, along with purslane, are two of the very few wild greens that are edible throughout the summer. You can pull off the tender last few inches of stem along with whatever leaves are there, and it will immediately branch and come back improved. If it's happy, it can get up to a meter and a half tall though usually it's shorter. Mine would get that high but I tend to keep it in check, otherwise I'd have nothing else growing in the garden. It produces a lot of seed. So much that I will not consider requests for seeds of these plants...I don't want to inflict it on the southern U.S.! Don't worry, plain old Love Lies Bleeding is every bit as good to eat, and actually preferred in many Greek gardens, where it serves as both an edible and as an ornamental. In Greece, it is known as "Vlita." Vlito is also a slang term for someon who is not too bright, due to the fact that if you eat a really large amount of it, it is said to make you a bit foggy-headed. I wouldn't know, pretty much any good meal does that to me anyway and I don't consider "food coma" to be an entirely bad thing!
You can use Amaranth in almost any way you'd use spinach - raw in salads, as a filling for pita (a friend in Naxos made a really nice "vlitopita") or boiled/steamed as a potherb and drizzled with olive oil and lemon. A little crushed garlic mixed in is not bad at all. Just be sure not to overboil it; just like spinach it will become mushy if overcooked but I think overcooked Amaranth is even less appetizing.
Today I made a very Turkish dish out of it - gözleme. It's a bit of work but not all that hard. I started with a plain dough of flour and water with a little oil mixed in and a bit of salt. It should be about the same consistency as bread dough or, as they say here, "like an earlobe." Knead it for around ten minutes, then cover it and let it rest. After 15 minutes or so, divide the dough into pieces about the size of a large egg and let rest again. (You might want larger or smaller, depending on the size of your frying pan.)
By the way, if you don't feel like dealing with dough, you could also take two flour tortillas and do this as a quesadilla. But it won't be nearly as good!
Meanwhile make your filling. Chop the amaranth leaves fairly finely. Chop an onion finely and sautee it, then add it to the Amaranth (the amaranth will cook later). The rest is up to you; I mixed in a handful of crumbled beyaz peynir, Turkey's take on feta cheese, some red flake pepper and some paprika, some salt and black pepper and that's pretty much it. You could also add kashar cheese, or boiled and semi-mashed potato.
Heat a heavy frying pan. In Turkey they use a "sac" (pronounced "saj"), like a shallow convex wok placed over hot coals. But a cast iron frying pan or griddle will do just fine.
Take a piece of dough, generously flour your counter and roll it out into a long oval about 1 mm thick. Here they use a thin dowel-like rolling pin called an oklava to do this, but you can do it with a regular rolling pin as well. You'll have to be a bit more patient though. Once it's open, take a generous spoon of the filling and spread it over half of the oval of dough, then fold the uncovered side over the filling. Press the edges to seal. Add a bit of oil to your pan, and put the gözleme in, and brush some more oil over the top. Once the bottom is browned, flip it over and cook the other side. Repeat with the rest of the dough. Gözleme filled with various fillings is a common wedding dish in E. Turkey, and I saw gözleme filled with Amaranth in the weekly market in Söke near Kuşadası. By the way, Kuşadası is pronounced "KOOSH a-da-suh," not "koosaDAWsee!"
Another great way to eat Amaranth is with eggs. Fry some onion in a generous amount of olive oil, add chopped Amaranth along with pepper if you like and saute till the amaranth is soft. Add salt to taste, then pour beaten eggs over the Amaranth, cover and let cook till the eggs are cooked through. Afiyet olsun!