Flatfish are plentiful and extremely popular in Scandinavia. They live all over the north Atlantic and Baltic and are caught in vast numbers, even if the population of the most popular fish have diminished.
Some flatfish, such as sole and turbot, are madly expensive, but the less well known species, such as flounder and dab, are even cheap.
Flatfish hatch as ordinary-looking swimming fish, with an eye on both sides, and live like this for a long time, until they gradually lose the swum bladder, one of the eyes wanders on to the other side of the fish, and it sinks to live the rest of its life on the bottom of the sea.
Some species have both eyes on their left others on the right, and as some species interbreed, there are lots of exceptions to the rules. Flatfish are almost indistinguishable from the sea bottom, and some have the ability of a chameleon to alter their coloring; when bathing it’s not uncommon to step accidentally on a brill or flounder.
Related: Scandinavian monkfish
Flatfish have beautiful, firm, moist and sparkling white flesh, except flounder, whose flesh is grey-tinged. They are usually lean, except for Greenland halibut.
Turbot and brill
These luxury fish are stars and need no fancy preparation to take away the attention. Turbot (Psetta maxima) is celebrated all over the world, but the turbot from the Scandinavian waters is the best. The cold makes the fish grow more slowly, and the brilliant white meat is dense, lobster-like and flavorful. Its close relative, the brill (Scropthalmus rhombus) is almost as good, and at a quite different price.
Don’t be put off by a very large brill or turbot; luckily some people believe that they become coarse with age, but this is not true, and it keeps the price of giant turbot at a more accessible level than of smaller fish. Brill is best in autumn.
Turbot and brill need particularly gentle treatment. Often they are baked in the oven with a knob of butter, until the flesh is almost done. If you cook them too much, the delicateness is gone and they will be dry. Cook them at 200C/gas mark 6 until the meat is still pink at the bone. Let them sit on the counter, covered in foil for a few minutes, and the heat from the pan will cook them gently through. Take away the skin and serve them simply, or with a topping of horseradish or chervil cream, caper or hollandaise sauce and horseradish.
There are two types of halibut, both giants of the north Atlantic. Halibut (Hippoglossus hippoglossus) can grow to an impressive ping-pong table size. The meat is delicious and meaty. Halibut is best eaten in winter.
Related: Scandinavian Garfish
The Greenland halibut (Reinhardtius hippoglossides) is small by comparison – up to 20kg, but usually weighing 1 – 2kg. It is not bottom-of-the-sea-bound like other flatfish, so both sides of the fish are usually colored. The flesh is fatty and lends itself beautifully to cold smoking ore home smoking. As with all fatty fish, you need to be very precise when you cook it – too long and it will be bone dry. The fish is fine all year round, but most exquisite in winter.
Speckled like a ladybird, with red spots on grey skin, plaice (Pleuronectes platessa) is the most loved fish for everyday meals all over Scandinavia. But it is not as plentiful as before and is quite expensive. The flesh has a tender sweetness to it, and is quite firm when cooked. Plaice is often served with rye flour and fried whole, on the bone, in butter. The fish is most delicious in late summer and autumn.
The flounder is similar in appearance to plaice, but with a knobbed back and no red spots, though the two species interbreed and it can be very difficult to know which is which. Inside, however, the flounder has dark, succulent flesh, with a taste quite different from plaice.
The with (a member of the flounder family) can grow to an impressive size, and is rarely eaten, but delicious.
The dab, not unlike a flounder in appearance, is normally what you get if you buy frozen flatfish fillets; it’s thin-fleshed and not too interesting.
At the other end of the scale, the delicious and expensive soles and lemon soles are mostly eaten in restaurants, and most of the catch is exported; their prices are simply prohibitive for private eating.
Flatfish cooked on the bone are much more succulent than fillets, but the latter are much easier to fry, simply coated in rye flour and sizzled in browned butter for a few minutes. Serve them hot on buttered rye bread with lemon and remoulade for a beautiful lunch dish. Other accompaniments might be potatoes and a variety of sweet-and-sour pickled things such as cucumber salad, raw lingonberry jam, and either just melted butter or a parsley sauce; but remember that the smaller flatfish, such as place and flounder are best in the summer, so don’t serve these with anything too substantial.
Larger flatfish, such as halibut and turbot, are wonderful if baked whole and served with a chervil cream, butter hand horseradish or a caper sauce.
The bones and heads of all flatfish are pure gold for fish stocks and fish soup. Keep them in the freezer until you have enough for a stock.
Scandinavian Flatfish, written by Tor Kjolberg