Leaf concentrate (l/c) is a nutritious food made by mechanically separating indigestible fiber and soluble anti-nutrients from the protein, vitamins, and minerals in fresh green leaves...The nutritional breakdown from the original work was that 20 grams of powder would provide 12 grams of protein. The amounts of vitamins and minerals (such as 440 mgs of calcium and 49 mg of iron) are impressive.
Sounds like a pain in the ass to make unless you have a juicer. You take your leaf juice, squirt it into boiling water and then skim off the resulting curd and dry it.
Still, it's probably a hell of a lot cheaper than vega or what have you and it contains plenty of high quality protein and loads of vitamins and minerals.