Amaranth leaves are found in abundance in the Tropics and growing up, I loved dal, tamarind stews, and yogurt stews made with them. It was only a few years ago, I started to use Amaranth grain or flour.
Amaranth is not really a grain, but a seed. It is highly nutritious, packed with protein, vitamins and minerals.
Here are some delicious recipes with this seed, flour or leaves that I posted previously:
Amaranth Leaves cooked two ways
The last few years I have been trying to grow Amaranth and Red Sorrel leaves in my patio garden, and it is challenging as well as highly rewarding!
Links:
Green
Patio Garden: Slow & Steady
Amaranth Plant
Amaranth Grain Nutrition
Health Benefits of Amaranth
Fly 'n Cook 