Back to basics: Fish

Here's everything you need to know to cook fish to perfection, every time.

The basics

Fish is the ultimate healthy fast food, with cooking times often under 15 minutes. It is packed with protein, vitamins and minerals. For general health it is recommended we eat fish regularly, including oil-rich varieties.

Here are the basics on how to get the most from your fish, with tasty ways to cook steaks and fillets. They are the perfect choice for spring when we feel like eating a little lighter.There are two important rules to remember with fish: buy it as fresh as possible, and take care not to overcook it.

Buying fish

• Really fresh fish is unmistakeable. Whole fish will look bright and fresh with vivid markings, clean shiny scales and bright eyes. The flesh should be soft and spring back when pressed.
• Fillets and steaks should look translucent rather than opaque. Avoid fillets if they look dry and shrivelled. A fresh, clean smell is another good sign. With the exception of shark and skate, fresh fish does not smell 'fishy'.
• If you buy your fish from a fish counter, don't be afraid to select your own fish. Remember, you can ask to have the skin removed.
• If buying fish pre-packed from the supermarket, check the sell-by date.
• If buying frozen fish, choose solidly frozen fillets in undamaged packs.

Storing fish

• Fish is generally best eaten within 24 hours of purchase. Oily fish goes off more quickly than white fish because the oils oxidise, causing the flesh to go rancid.
• To store fish, remove it from its wrappings, rinse it under cold water and pat it dry. Rewrap the fish loosely in a plastic bag and store it in the coldest part of the refrigerator.

Healthy ways to cook fish

Cooked to perfection

One of the worst things you can do to fish is over-cook it. Steaks and fillets will cook very quickly. Properly cooked fish is moist, tender to the bite and full of flavour. Fish is fully cooked when the colour turns from translucent to opaque (usually white). Test the fish when it begins to look opaque. Gently prod it with the prongs of a fork: when the flesh will flake easily, the fish is done.

Baking

• Place fish fillets in a shallow dish with fresh herbs, seasoning and a splash of white wine and fish stock. I use Essential Cuisine fish stock; it has no added salt and is 99% fat-free. Cover and bake at 180°C. Fillets and steaks will take between 15-25 minutes.
• Fresh red and blue cod, gunard, snapper, hapuku, hoki and salmon are perfect for this type of cooking. Sealord's frozen fillets (dory and ling) are also ideal.

Baked-in-the-bag fish

This method of cooking works well with salmon, cod and gurnard; toss in a few prawns and scallops for deluxe seafood parcels.

1. Cut greaseproof paper into a 26cm square and scrunch together in a small bowl. Pour over a little wine and leave to soak for 1 hour; push the paper down in the wine occasionally.
2. Open up the greaseproof paper and place your fish steak on top. Sprinkle with some fennel seeds, top with a lemon slice and a dill sprig (optional). Season. Drizzle over a little wine.
3. Seal the fish in the paper parcel by twisting both ends of the paper to enclose the fish and form a parcel. The parcel is now ready for cooking. Cook at 200°C for 15 minutes.
4. The baked parcel will be splattered brown from the wine and fish juices. Take care when unwrapping the parcel as hot steam is released.

Grilling

• This is a very quick and easy way to cook fish. Before you start cooking, line the grill pan with foil to prevent lingering fish smells. If cooking thick fillets with skin on, slash the skin several times with a sharp knife so that the heat can penetrate.
• Chopped fresh herbs, a little olive oil and plenty of coarsely ground black pepper will enhance the flavour of your fish, especially if you leave it to marinate in these ingredients for half an hour or so before cooking. Turn occasionally.
• Salmon, swordfish, tarakihi and tuna are all good choices. Brush occasionally with oil or marinade to prevent fish drying out. Barbecued fish can be prepared in much the same way as for grilling. Choose groper, tuna, monkfish, mackerel, ruby fish, snapper and shark.

Griddling and pan-frying

• When cooking fish steaks in a griddle it is important to spray the pan evenly with a little oil. Heat the pan until very hot. Add the fish steaks and cook over a high heat quickly either side. This is called searing. Tuna steaks need between 30 seconds-1 1/2 minutes each side. Tuna is ideal cooked in this way as it can become very dry if overcooked. Other chunky steaks work well but take care with white fish as it is quite delicate.

Microwave cooking

• Fish is excellent when cooked in the microwave, retaining all its delicate texture and shape as well as its natural juices. It can be cooked with no added liquid so there is less loss of nutrients.
• Fish steaks and fillets are most suitable to cook in the microwave, because they cook quickly and evenly. Steaks should be laid in a round dish with their thinner ends facing inwards. Fillets should be placed in a single layer, folding the thinner ends underneath so they do not over-cook. Sealord's frozen fish selection is a great choice for convenient, quick fish meals in minutes. Cod, hake, hoki, kahawai and skate are excellent cooked in this way.

Steaming

• Any fish fillet or small whole fish can be steamed. Add richness of flavour by using a well-flavoured fish stock and rest the fish on a bed of herbs.
• Bring the liquid to the boil then reduce the heat to simmering point. Lay the fish fillets in the top of the steamer, making sure they do not overlap or they will not cook evenly. Place it over the liquid and cover. Steaming times vary with the size and quantity of fish: allow 5-8 minutes for fillets, 10-15 minutes for steaks.
• Smoked fish such as cod is a good choice.

Casseroles and stews

• For fish casseroles and stews, choose gurnard as it is tasty and has a firm flesh. Hake, kingfish and lemonfish are other good options.

Simple ideas for fish steaks

• Gremolata is a fantastic topping to add to grilled fish. Simply blanch 2 garlic cloves in boiling water for 3 minutes, then crush. Add the rind of 1 lemon with 2 tablespoons finely chopped parsley and mix. Season to taste and sprinkle over grilled steaks.
• A simple tomato sauce is a perfect topping on white fish. Gently fry a finely chopped onion with a crushed clove of garlic in a tablespoon of olive oil until softened. Add 2 tablespoons of sun-dried tomato paste, 2 teaspoons of sugar and a can of chopped tomatoes. Heat for 6-7 minutes. Season with pepper and some fresh herbs of your choice. Spoon over white fish fillets and bake. Alternatively, serve on cooked steaks.

Quick fish tips

• For convenient sources of omega-3, choose Sealord dory frozen fillets or tarakihi fillets in your supermarket. They are ideal for barbecuing, oven baking and microwave cooking, and are fantastic for fish curries and stews.
• For the ultimate fish salads, Regal smoked salmon is a favourite choice for me. Serve it with a mix of salad leaves, cherry tomatoes and sliced avocado. Finish off with a squeeze of lemon juice. Season with black pepper and serve with fresh crusty bread.
• Try the smoked salmon morsels which are ready to eat and make a perfect appetizer with some low-fat tzatziki; low-fat natural yoghurt mixed with some crushed garlic, a pinch of salt and some chopped fresh mint. Serve with a finger bowl or thread the morsels onto skewers for mini kebabs.

White fish and oily fish - what's the difference?

• White fish are salt water fish with oil concentrated mainly in the liver. The two main groups are the cod family, which includes blue cod (also known as raawaru, New Zealand cod and sand perch) and red cod. The other is the flatfish family of brill, plaice, sole and turbot. Other white fish include John Dory, flounder, monkfish, skate and snapper.
• The oil in oily fish is distributed throughout its flesh. This makes it a better source of good omega oils than white fish. Salt water oily fish include herrings, mackerel, sardines and tuna while salmon and trout are oily freshwater fish.