Fresh mushrooms are often dirty and need to be cleaned before use. The easiest way to clean mushrooms is with a fine pastry brush. Morels may contain soil and small stones, which can be easily removed by cutting the mushroom in half.
Dried mushrooms should be soaked in water (room temperature) for at least 15 minutes before use. Frozen mushrooms are best cut once they are partially (but not fully) defrosted.
Throw away any mushrooms that are moldy, contaminated by insects, past their best or damaged. Fresh mushrooms can be identified by their fresh, specific smell and their smooth, unmarked surface. Mushrooms should never be watery or grey in colour.