Porcini mushrooms (Boletus edulis) are considered superior in flavor and texture. Its Italian name means “Little piglets,” which describes its appearance with pudgy stalks and rounded brown caps. Its flavor is earthy, nutty and slightly meaty, with a smooth, creamy texture. Porcini are prominent in Italian cuisine and are widely exported and sold in dried form, reaching countries where they do not occur naturally.
When purchasing fresh porcini mushrooms, look for ones that are firm, with white stalks and brown caps that are not nicked or broken. If the undersides of the caps have a yellowish-brown tinge to them the mushrooms are beginning to decay. Also avoid any with black spots on them or the under caps are deep green. The other thing you should look for in a tired mushroom is signs of worms. When you get home, scrape any dirt you may find off the stalks and wipe the mushrooms clean with a damp cloth.
If you purchase dried porcini mushrooms, which are widely available in larger U.S. grocery store chains, look them over carefully. If they’re crumbly they’re likely old and probably won’t have much flavor. Also, look the mushrooms over for pinholes, and if you see any, check the bottom of the package for worms. If you find any worms, it’s better to discard the package. To prepare dried porcini steep them in just enough boiling water to cover for 20 minutes or until they’ve expanded. Drain them, reserving the liquid, and mince them. They’re now ready for use. I use the liquid as well, substituting it for any other liquid called for in the recipe.