Brief Introduction of Shiitake:

Shiitake is grown on oak logs in the wild, hence its name "Shii" (oak tree) "take" (mushroom). In the more modern mushroom farms, Shiitake mushrooms are grown in plastic-bag logs filled with wood substrate and have become one of the most popular cultivated mushrooms. It is known to enhance the immune system, aiding the body to fight infection and disease, and is gaining ground in the medical world for its anti-tumor qualitites.
 
Popular in Asian cuisine for centuries, it has gained popularity in the United States, where it's added to salads, soups and pastas. It's also meaty and flavorful enough to be used as the primary ingredient in sandwiches. Dried shiitakes can be stored in the freezer for up to six months.