How to handle Shiitake mushroom before cooking

Shiitake mushroom is popular in Chinese cooking. The mushroom itself consist of cap and stem. We usually only use the cap because the stem is too hard.

There are two forms available in market: dried and fresh. Today I used fresh shiitake mushrooms for cooking. So actually I just need to wash them. Out of habit, I soaked them in fresh water.  

Dried mushroom is very hard. It is usually prefered because, according to wikipedia, the sun-drying process draws out the superior umami flavour from the dried mushrooms by breaking down proteins into amino acids. To soften it, it must be soaked in hot water for at least 30mins before cooking.