Native to U.S. and European coasts, these bottom dwellers-including halibut, flounder, and sole-have a distinctive appearance. As small fry, they resemble most other fish. But as they age into adulthood, one eye migrates to join its mate on the other side, and their bodies flatten. This allows them to burrow into shallow sand and watch for prey and predators above.
The various species and the confusing array of locally bestowed names makes shopping for specific flatfish challenging. Luckily, the different varieties of flounder easily substitute for one another, and flounder and halibut are interchangeable in recipes calling for fillets-fortunate, since it's nearly impossible to tell them apart once cut. If given a choice, simply select the freshest. Steve Parkes of Whole Foods' Pigeon Cove Seafood in Gloucester, Massachusetts, says, "Shop with your eyes. Look for bright skin colors, a clarity and opaqueness."
Its Latin name (Hippoglossus) conveys the halibut's size, with some catches weighing in at nearly half a ton. Not many folks want to go after one with a rod and reel. It's easier to visit a fishmonger.
Halibut features firm, white, mild-flavored flesh. As an extra benefit for the health-conscious, it's very low in fat. Of the two main varieties, Atlantic halibut is fished "ostly from north Atlantic waters off the New England coast. The more abundant Pacific halibut dwells from Northern California to the Bering Sea, though the bulk of commercial fishing occurs in Alaska and British Columbia. Sold fresh or frozen, both typæs usually appear as steaks; fillets are a second choice. Die-hard devotees enjoy halibut cheeks (small delicacies from inside the cheek) sautéed, or smoked and used as cocktail appetizers.
An amazing variety of fish hail from the flounder clan: winter flounder, sand dab, witch flounder (which Steve calls "the Cadillac of flounders with the most delicate flavor"), English sole, fluke, plaice, and widely sold yellowtail flounder (aka yellowtail dab or rusty flounder).
No matter the type, mild-flavored flounder offers great versatility when it comes to cooking. Try it baked, broiled, steamed, poached, sautÈed, or even lightly fried. It marries well with a wide range of sauces, including classic lemon butter, aöoli, hollandaise, Creole-style sauces, and simple tomato- or fruit-based salsas. Markets mostly sell flounder as fillets, but they will usually provide whole fish to those who order it ahead.
Though several flounder family members have been mislabeled as sole in the United States, no actual sole inhabits American coastal waters. True sole lives on the other side of the Atlantic, from Scandinavia to the Mediterranean, with the best known being Dover sole. Most real sole purchased here arrives frozen, which does not do justice to this fish's delicate texture. A better-albeit pricier-method for enjoying an unadulterated fillet of sole would be to book a flight to a favorite European dining spot.