Snap off the stem of a thin-capped shiitake mushroom.
Place it cap-down in water.Submerge the shiitake evenly by resting a piece of food wrap directly on them in the water.
After 5 to 10 minutes, cut the shiitake in half with a knife.Cut off the remaining stem.Water will soak into the shiitake quickly from the freshly cut surfaces.
If it is soft enough, you can go ahead and cut the shiitake to your desired shape.The smaller it is cut, the faster it will return to its original texture.
When the shiitake has been submerged for about 20 minutes, it's ready for use in cooking. (For thicker Donko shiitake, you should let them soak slowly overnight.)