The popularity of sole dates back at least to the ancient Romans, who called it solea Jovi (Jupiter's sandal), undoubtedly because of the elongated-oval shape of this flatfish. Though a number of flounder family members (such as Petrale sole, lemon sole, rex sole and butter sole) are incorrectly called sole in the United States, the highly prized true sole is found only in European waters. The best-known of these is the Dover sole (also called Channel sole), which is found in coastal waters from Denmark to the Mediterranean Sea. The body of the Dover sole averages about a foot long and ranges in color from pale gray to dark brown on the top side, with the underside a pale beige. Its delicately flavored flesh has a fine, firm texture. True Dover sole is imported frozen to the United States from several of the northern European countries and is available in better fish markets. Other true sole include the thickback and the sand (or partridge) sole, both smaller and less flavorful than the Dover. Much of what is sold as Dover sole in the United States is actually flounder. Sole can be prepared in a variety of ways including poaching, steaming, baking, broiling and sautéing. It's ideally suited for combining with other foods and sauces. See also fish.
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.