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Cooking Basics

You can count on Peter Baldwin and his team of chefs from Shepherd Neame's Fish on the Green in Bearsted, Kent. They have put together some basic cooking advice so you can easily add local seafood into your weekly diet. It can be easier to cook fresh fish than chicken nuggets when you know how. Using locally sourced, seasonal seafood is sustainable too. 

You don't need to be a professional chef to cook great seafood

Is it fresh?

Properly handled and stored, a fish will stay fresh for some days after it’s caught (up to 10 days for some species).

A good fishmonger is unlikely to sell you old fish, but some guidelines for spotting freshness will make you a more confident fish buyer.

A fresh fish should:

  • Have intact scales
  • Have clear, bright eyes that are still convex, not sunken
  • Be red under the gills, not brown
  • Smell of the seaside – fish smell fishier as they get older

To keep your fish fresh, take a cool bag or cool box with you and ask the fishmonger to put a few scoops of ice into a plastic bag to pack around it. When you get home, put it in the fridge on a plate, loosely covered with a cloth. You can keep it like this for up to 36 hours, but to make the most of your fresh fish, eat it on the day!

How to Buy

Choosing fish sustainably.
The essential thing is to eat what’s in season and your fishmonger will be able to give you advice. You can also buy sustainably by being adventurous and choosing widely from what’s available, instead of sticking to familiar favourites like cod. If we eat a wide variety of species, that keeps the pressure off popular species and allows fish populations to stay at a sustainable level.

Get to know your fish supplier.
They will be able to tell you where the local stocks have come from and what’s fresh. Finally, make sure you are following the official guidelines for safe travel and distancing whilst buying your fish.

How much should I buy.
Fish will shrink a bit when you cook it, but if buying fillets or steaks, what you see in the shop will be roughly what you end up with on your plate. If you’re buying by weight, a whole fish will yield about 50% of its weight in fillets (less if it’s a large-headed fish like a gurnard, more if it’s something really meaty like a monkfish).

Tricky-looking fish.
Don’t be put off if a fish looks difficult to work with - your fishmonger can help (see next section)


I’m sure there are a lot of people who are put off buying and cooking fresh fish altogether by the idea of having to gut and fillet it.

Fortunately, you don’t have to do this – fishmongers will prepare your fish for you, quickly and expertly, so you can buy whatever’s in season and sounds delicious.

  • If you ask the fishmonger to fillet a fish for you, he will cut off the main section of flesh from each side.
  • If you’d also like the skin taken off, you can ask.
  • Likewise, if you’re a really keen cook and want the bones and head for stock, say, just ask.
  • If you’re buying whole fish, it may well already be gutted but it is worth checking.

Finally, fishmongers are knowledgable so don’t be afraid to ask for cooking advice, too.


UK waters are also home to lobster, crab, langoustines, oysters, mussels, cockles, clams… Many of us have happy memories of eating or even catching shellfish at the beach.

However, there are some things that can put people off about preparing shellfish, especially worries about seasonality and safety.
You can buy shellfish fresh or ready cooked from your fishmonger (including lobster and crab already cooked). As with fish, a fishmonger will know what’s in season and at its best, and can help you with preparation and cooking tips.
Shellfish such as mussels, cockles or clams should be avoided when they are spawing, generally May to August, and shouldn’t be on sale in these months. Lobster and brown crab are in season during these months, however, so are a good choice for the summer.

Mussels are common all around the coast of the British Isles, both wild and farmed but should be avoided when they are spawning from May to August. Make sure the mussels you buy are tightly closed and avoid mussels that are covered in mud. If you have any that are open by the time you get them home, give them a tap and they should close, if not discard them. Similarly, if a mussel doesn’t open during cooking, discard it. This simple rule also applies to cockles and clams. Mussels can be stored at the bottom of the fridge covered in damp newspaper for up to 24 hours.


In today’s world, the speed and ease with which you can cook a piece of fish is invaluable.

Roasting fish in the oven couldn’t be simpler – cut a few slashes in the sides of a whole fish about 450 g/1 lb in weight, lay it in a large roasting pan, then rub a sprinkle of salt and some olive oil into the skin. Cook in a preheated oven for 15–20 minutes while you have a chat and make something quick to go with the fish – salad or veg, fresh bread and butter.

The temperature guide is easy, you just have your oven preheated and set to maximum (200⁰C+). This way the fish is cooked quickly and the moisture is retained, as the fast heat drives flavour and moisture from the central bones.

You can cook fish fillets exactly like this too – in the oven with some olive oil and a little salt - but for less time, say 8 minutes.

If you’d like to add more flavour, garlic, fresh herbs – rosemary, basil and oregano – and lemon all make a fabulous fish supper.


The same rules apply to grilling fish – quick cooking under fairly high heat with olive oil and salt.

You will know when it’s cooked when it is just opaque (not translucent as it is when raw).

If you are grilling or barbecuing a large piece of thick fish, start it under the grill or on the barbecue and then finish it in a hot oven for five minutes.

In the Bag

Cooking fish in a bag is also very easy to do and the results are impressive.

You can prepare some incredible recipes from just a few simple flavours, such as sea bass with ginger, soy and spring onions, or sea bream with roasted thyme, garlic and chilli.

That said, you can also keep it very simple, adding a little oil, salt and pepper to the fish – maybe a drop of wine, or some fresh green herbs such as parsely or, for more fragrance, coriander.

The bag can be made of foil or baking paper, formed into an envelope or pouch and sealed by folding. You can cook a whole fish or pieces of fish this way. Leave some room around the fish and leave an opening for steam to escape and put the whole thing on a baking tray or in a roasting tin. (Also be careful of steam when opening the bag).

Temperatures and times are the same as for roasting.

Place in a hot oven (200-220⁰C), for a cooking time of about 20 minutes for a whole fish or 12-14 minutes for a main-course sized fillet or steak.


Yes! You can microwave fish.

Fish is such a healthy food and can be delicious however it’s cooked. If microwave is your only option, fish can still be for you.

Put a fillet of fish on a microwave-proof plate with some butter (to taste, but perhaps start with a blob or two about the size of a dice), seasoning and a small handful of herbs, cover with cling film and ping. It should take 3-4 minutes on high.

You can also make a nice sauce using Chinese flavours like soy, water ginger and garlic - just put them in a bowl with the fish, and cling and ping as above.

Lobster and Crab

To cook a lobster, bring a large saucepan of salted water to the boil, add the lobster and cook for 10 minutes (this will vary by weight, roughly 10 minutes per 450g/1lb and 3 minutes on top for each additional pound). Remove the lobster from the water and leave to cool, before cutting in half lengthways from head to tail, removing all the meat and picking all the meat from the claws.

The method is the same for a crab. Bring a large pot of well-salted water to the boil. Add the crab to the pan and boil for about 15 per 1kg (2lb), adding more time for more weight. Remove from the water and stand on its nose to allow the water to drain away as the crab cools. Once cooled, remove the legs and claws by pulling them off from the body. Place the crab on its back (hard shell-side down), put your hands under the edge of the crab and push upwards until you hear it break. Lever the crab apart. Remove the spongy ‘dead men’s fingers’, stomach sac and hard membranes and discard. Use a spoon to remove the brown meat from the shell. Break each claw in half and scrape the white meat out of the thick end of the claw. Use the back of a heavy-bladed knife to crack open the remaining claw and the pincers. To remove the meat from the body of the crab, take a sharp knife and cut the crab body in half then in half again. Pick out the meat using your fingers.

A fine and simple way of enjoying crab is a simple crab sandwich. To make this, spread some mayonnaise onto a piece of good brown bread, place some brown crabmeat on top, then add a layer of chunky white crabmeat, some sliced cucumber and a sprinkling of cayenne pepper and lemon juice and sandwich between the other piece of bread – fantastic!

Pan Frying

Use a paper towel to pat the fish dry on both sides and try to remove any small bones. Season the top/skin of the fish generously with salt and pepper. Warm some oil or butter in a skillet over a medium-high heat. The pan is ready when a flick of water sizzles on contact with the pan. Lay the fish, seasoned/skin side down, in the pan.

Cook the fish for 2 to 3 minutes without moving it. When ready to flip, the underside should look golden and crispy. It should also release fairly easily from the pan using a fish spatula. While the first side cooks, season the other side with salt and pepper. Flip the fish to the second side and cook for another 2 to 3 minutes. When ready, the fish will be opaque all the way through and flake apart easily.

Serve the fish while still hot from the pan with any finishing garnishes. White fish can often be very flaky after cooking; don't worry if it flakes apart a bit as you serve it.


Air fryer

Pre-heat Air Fryer to 360°F/185°C for 5 minutes. Rinse and pat dry the fish. Remove any small bones. Season with salt and pepper. Lightly spray the air fryer basket/rack or lay a perforated parchment sheet or silicone mat. Air Fry at 360°F/185°C for about 9 minutes, or until fish can be flaked with a fork. Timing will depend on the thickness of the fillets


Some fish fillets are thicker than others, so if air frying with a thicker fish steak, add an additional 1-2 minutes until it’s cooked to your preferred texture.  If you’re air frying in a larger air fryer with multiple fillets (3-4), then you will need to add a bit more cooking time too