Most mushroom varieties grow in overgrown, high humidity forest areas. As a result, they are usually harvested with a good amount of mud and dirt on them. Wiping them one at a time with a moist paper towel is one way to clean them, but it can be tedious and time consuming. You'll be happy to know that you can actually wash whole mushrooms by quickly rinsing them under cool tap water! However, avoid washing cut mushrooms. Mushrooms are like little sponges so when they’re cut, they absorb a lot of liquid when exposed to it.  Whole mushrooms won’t absorb liquid easily or quickly. So you can quickly rinse whole mushrooms under cold water and wipe them with a paper towel right away. This will save you some time in preparation.