Preparation:
Under running water quickly wash the mushrooms. Just before cooking, cut off and discard, if any, the brown part of the end of each stem. Slice lengthwise through the stem and into the cap, keeping each slice in the shape of a mushroom. You should have about 6 cups.
Cooking:
Heat a wok until very hot. Add the oil and stir-fry the mushrooms over medium heat for 10 minutes. Add either the soy sauce or salt. Stir 5 more minutes until the liquid evaporates. Let cool.
To store, keep the mushrooms submerged in the oil in a covered container. The mushrooms can be kept in the refrigerator up to 2 weeks.
