How to buy, prepare and cook fish and seafood properly

Fish and seafood is full of protein, low in fat and quick to cook. Here’s how to make the most of delicious seafood

Matt Owens is National Chairman of the Craft Guild of Chefs, which supports chefs with training and development. He shares his advice on sourcing, preparing and cooking seafood to perfection.

How to buy fish

Use a reputable supplier to get the freshest fish and buy what’s local and in season where possible. Whole fish should have clear eyes, bright blood under the gills, moist skin, and a firm tail and flesh. It should smell of salty seas — not fishy! Sustainably sourced fish is essential. Look for MSC approval or ask your supplier how the fish is caught. Don’t just rely on cod and salmon, try sustainable alternatives including sardines, mackerel, pollock, basa or tilapia. They deliver great flavour and better margins too.

How to prepare fish and seafood properly

Fillet fish

Use fresh fish, as it fillets better. Run a filleting knife along one side of the spine, then from head to tail to remove the fillet. The knife should run against the bones so you don’t cut into the flesh.

Remove skin

Put the fillet skin-side down. Slide the knife between the skin and fish, holding firmly onto one end. Cut horizontally away from you and push down onto the board to stay close to the skin.

Clean mussels

Discard any open mussels and soak in cold, fresh water to remove grit. Pull the hairy ‘beards’ off and use immediately. After cooking, discard any mussels that haven’t opened.

Peel prawns

Freshness is key. Peel shells off from the underside, as though taking off a jacket. Use a sharp paring knife to remove the bitter back vein. Use shells for stock.

How to cook fish

Remove fish from the fridge 10 minutes before cooking, so the muscles don’t seize in the pan. Fish can easily overcook: white fish turns translucent when ready and salmon or trout can be served slightly pink. Most fish are versatile and suit multiple cooking methods.

Pan-fry

A quick-cook method for most fish. Place skin-side down in a hot pan to crisp up; wait until it’s cooked halfway through before flipping. Great for bass, salmon, halibut, or tilapia.

Poach

A delicate way to cook all fish. Poach fillets in a creamy or tomato sauce in a covered, shallow pan or hot oven for 10 minutes.

Roast

Meaty fish without too many small bones including whole bream, sea bass, snapper or salmon are great cooked in the oven. Roast in a tray for crispy skin or wrap in greaseproof paper and stuff with lemon and fennel for Mediterranean flavours.

Curry or stew

Use flaky, firm seafood such as gurnard, haddock or prawns. Dust pieces in spiced flour and pan-fry before adding to the stew or curry in the last 10 minutes. This thickens the sauce and avoids overcooking.

Grill

Best for small or flat fish (mackerel, sardines, sole, skate), fattier, robust fillets (salmon, trout, and tuna), or smoked fish (kipper or smoked haddock). Robust or oily fish also BBQ well.

Matt's top tips

1 FRESH OR FROZEN? When fish is frozen at sea, it’s the same quality as fresh, as the taste and nutrients are captured immediately. Fish on the counter is often defrosted, so buying frozen actually increases shelf life for you, plus it’s frequently better value.

2 GOOD VALUE BUT IMPRESSIVE Less is more when flavouring fish: a squeeze of lemon, parsley gremolata, or browned butter garnish feels premium.