Fish is the ultimate fast food – steam, bake, grill, poach, fry, stir-fry, microwave, stew or barbecue it.
How to know when fish is cooked
Fish turns from translucent to opaque when you cook it so cutting a slit in the fish and looking at it is the best way to check its ‘done-ness’. You can also stick a skewer or sharp knife into the thickest part of the fish to see if it comes out clean (just as you would with a cake).
Steaming is a good way to cook delicate fish or shellfish. Use a bamboo or metal steamer: place the fish on an oiled plate or a piece of oiled tin foil and insert into the steamer basket, leaving space for the steam to get through from below. It usually only takes about 10 to 15 minutes for an average-sized fish but you will need to check it as it cooks (see note above). You can sprinkle chopped spring onions, ginger or garlic on top of the fish before you cook it and add a little sweet mirin, fish sauce, white wine or other liquid to add flavour.
A really easy way to cook fish is to bake it – place the fish in an oiled ovenproof dish with a little liquid (water, stock or wine), dot it with butter, season with salt and pepper and bake it in a hot oven for 15 to 30 minutes depending on size. You can also sit the fish on a bed of vegetables, say sliced fennel or onions, to save it from getting too much direct heat from the bottom of the dish. Alternatively, wrap the fish loosely in tin foil or parchment paper with a little of the flavouring liquid, some finely chopped chilli and a few herbs. You can also cover fish fillets in a bechamel sauce (add any leftover grated cheese to the sauce) and top with herby breadcrumbs and bake until bubbling and golden.
Grilling fish is a healthy way of cooking fish. It can smell out your grill, so immerse the grill pan in hot soapy water immediately after use. If you are grilling fish, make sure that you can remove it from the rack easily by brushing the fish with olive oil first – if the fish is very thin and delicate, line the rack with oiled tin foil. Use a large flat spatula to turn the fish so it doesn’t break. If you are cooking whole fish, cut slits in the thickest part to make sure it cooks evenly.
This is when you cook fish in liquid. You can do it with white fish or shellfish. Just put the fish in a saucepan or frying pan with a little stock or milk and simmer gently (never boil). Add flavourings like a bay leaf or herbs or a few black, green or pink peppercorns. You can strain the poaching liquid and use it to make a bechamel sauce with white wine and herbs. You can also poach smoked fish in milk, water or stock – the resulting liquid will be strongly flavoured and salty so you may not be able to use all of it in the final dish.
This is the least healthiest way to cook fish, but probably the one that we remember most from childhood. The fish is often protected by a batter, or by a coating of flour, to stop the heat from damaging the fish. You can shallow-fry fish in a little olive oil or deep fry (for battered fish) in oil or lard (many Dublin chippers fry their fish and chips in lard, if you leave the chips to go cold, you can taste the fatty deposit on the chips that you don’t notice when they are hot). When frying fish, you need to ensure the oil is hot enough so that the fish doesn’t soak up the oil, then drain the fish well and dry it in paper towels (a rule of thumb is that the oil is hot enough if you can fry a day-old bread crouton in oil and it turns brown between 30-60 seconds). Stir-frying, where you move the fish about quickly in a little hot oil, works well for shellfish and sturdier fish like monkfish that won’t break down during cooking.
One of the best ways to cook fish if you are trying to lose weight, or eat more healthily is to microwave it. It also underpins fish’s reputation as the best fast food. Season the fish, place it in a microwave dish, making sure the fish is flat in the dish, so that all of it cooks evenly. Leave the fish to stand when you take it out, as you would all microwaved food. To find timings, check your microwave recipe cookbook.
This is where you cook the fish in a saucepan or casserole as part of a stew. It suits firm fish like monkfish or turbot. You still can’t cook the fish for a terribly long time as you would a meat stew, or the fish will break down in the liquid – it’s best to add the fish near the end of cooking.
It’s best to barbecue whole fish, or sturdy fish like salmon cutlets or monkfish which can stand up to the heat. Fine delicate fish like plaice needs to be baked over the barbecue in tin foil to save its soft flesh from disintegrating (add a little liquid to keep the fish moist) . Oily fish are great for the barbecue as they stand up to the strong flavour that barbecues impart to food, and the oil helps them to cook and to keep them moist. You can get a wire basket for whole fish that gives an attractive pattern to the skin’s fish when the heat sears it. Shellfish are great for the barbecue, especially prawns in their shells.
Often called sashimi, or made into rice rolls called sushi in Japanese cooking, you need to be careful where you get your raw fish from. Only buy it at its absolute freshest and make sure that it is sashimi quality. It’s probably safest to eat it at a reputable restaurant if you can’t find a source of very fresh fish.