Fish is the thing most people say they never cook at home. It is seen as expensive, easy to ruin and smelly. In practice it is the fastest protein there is, almost impossible to get wrong once you know the single test for doneness, and the cheap versions are the best value protein in the shop.
Three methods cover nearly everything
Pan: hot pan, dry fillet, skin side down in oil, press it flat for ten seconds, then leave it alone for three or four minutes. Turn once, thirty seconds, done. Do not move it around. Oven: on a tray with oil, salt and lemon, at a high temperature, eight to twelve minutes depending on thickness. This is the method that never goes wrong. Poached or steamed: in barely simmering water, stock, milk or a sauce, with a lid on, for five to eight minutes. The gentlest and the most forgiving, and it makes its own sauce.
The one test for doneness
Push the tip of a knife into the thickest part and twist gently. If the flesh separates into flakes rather than resisting, it is done. If it still holds together as one piece, give it another minute. Fish continues cooking after it leaves the heat, so take it off while it is barely done. Overcooked fish is dry and chalky, and that single mistake is behind almost everyone’s dislike of home-cooked fish.
Frozen and tinned are not lesser
Frozen fish is usually frozen on the boat within hours of being caught, which is fresher than the fresh counter in most inland shops. Cook it from frozen in the oven or thaw it overnight in the fridge; never in water. Tinned sardines, mackerel, anchovies and tuna are among the cheapest good protein available. Sardines on toast with lemon and pepper is a genuinely good dinner and costs almost nothing.
The smell is a solved problem
Fresh fish barely smells; a strong smell means it is old. Buy from somewhere that smells of the sea rather than of fish, and cook it the day you buy it or freeze it. When cooking, an extractor or an open window and a pan of lemon peel simmering afterwards takes care of the rest. The lingering smell comes from fish cooked slowly in a closed room, not from fish cooked hot and fast.
What to serve it with
Anything acidic and anything green. Lemon, vinegar, capers, pickles, herbs, a sharp salad. Fish is mild, so it needs the plate around it to be sharp. Potatoes, bread, rice and beans all sit under fish perfectly. It needs almost nothing else, which is another reason it is a weeknight food rather than an occasion.
Pan, oven or poach. Cook it hot and briefly, twist a knife into the middle to check, and stop while it is only just done. Fish is the fastest dinner in the house, not the most difficult.