Grifola frondosa is its botanical name, and it is indeed at the top of the mushroom chain -- medicinal and delicious!  I discovered maitakes at a farmers market; a mushroom vendor urged to me take one home and chop it up and saute it ... Wow, is all I had to say, and I have been eating it ever since.  (Chop or dice and saute lightly in coconut or other oil, add sea salt and use as a crumble on just about anything.  You can freeze what you have cooked and use a little every day; your body will love this stuff!)

Okay, so what is the maitake?  It grows wild in the forest at the bottom of great old trees (oaks and elms), feeding on the dying roots.  Maitakes can reach tremendous size (30-50 pounds), but the cultivated versions can be held in your hand.  Mushrooms are the fruiting bodies of fungi, and if you study the trophic chain, fungi are decomposers, rendering dying life into earth nutrients to begin the chain all over again.  This article covers the many health-boosting properties of maitakes, which some people consume in powder or capsule form.  Nothing is as good as the food itself, and certainly not as tasty, for maitakes create umami -- also known as "the fifth taste" -- an experience we don't often get.  Growing in popularity, you can now find organic maitakes at stores like Whole Foods; they are "air-packaged" in puffy cellophane pouches, so this is what you have to look for in the mushroom section.