Also called cèpes, these delicious earthy treasures are members of the Boletus edulis species of wild mushroom. They're pale brown in color and can weigh from an ounce or two up to a pound. Their caps can range from one to 10 inches in diameter. Porcini have a smooth, meaty texture and pungent, woodsy flavor that is much regaled. You'll seldom find them fresh in the United States, but you might try looking for them in specialty produce markets in late spring or in the autumn. If you get lucky, choose those with firm, large (about six-inch) caps and pale undersides. The dried form of this mushroom is more readily available. Choose those that are a tan to pale brown in color; avoid those that are crumbly. Dried porcini must be softened in hot water for about 20 minutes before using. They can be substituted for cultivated mushrooms in most recipes. One ounce of dried mushrooms will serve about four people in soups, stuffings, stews and the like. Porcini are also known as Boletes and Steinpilze.
From The Food Lover's Companion, Fourth edition by Sharon Tyler Herbst and Ron Herbst. Copyright © 2007, 2001, 1995, 1990 by Barron's Educational Series, Inc.