Mark Hix experiments with some sustainable fish

We are regularly told to eat more fish - it's good for us, it's healthy, and it contains essential oils. All that's absolutely fine and yes, we should include more of the stuff in our diets, but what about the poor old fish? We hear so much these days about the depleted stocks of fish in our seas which is caused by our consumption. Some years ago, when the word got out that fish stocks were in danger, we started to buy fish such as hoki because there was plenty to go around, and it was marketed as a good replacement for cod (well, kind of - if you covered it in batter or curried it; I was never quite convinced). But recently I read in an Aussie newspaper that hoki is now on the endangered species list.

So who should we listen to? When I was a kid, rock salmon was a popular fish and chip shop treat in the West Country, but the problem with rock salmon was its misleading alias: we knew it as dog fish or huss. The dog fish used to plague our live bait when we were fishing off the coast and we often ended up returning more than we kept. You would think that dogfish was not an endangered species, but according to the Marine Conservation Society's good fish guide ( they have in the past been over-exploited in the north Atlantic and supplies came close to collapse.

That's the problem with the less common species: pollack, gurnard, sprats, mullet, flounder and mackerel are all harder fish to sell because we all want to eat prime fish such as cod, bass and salmon. We know what they taste like and they're expensive - apart from salmon, the farming of which has become so commercialised that it costs next to nothing and tastes of nothing much either.

But imagine if your local fishmonger stopped serving cod and bass and started selling pollack and grey mullet instead - and when I say selling I don't mean leaving it unattended on the slab but actually talking it up and telling us how to cook it and what it tastes like. My theory is that if a lot of that second and third division fish was more expensive, it would be more marketable. Everyone knows the monkfish story. When I was a kid the fisherman couldn't give it away, and by the time I'd moved to London to work in hotels it had moved up into the premier league.

The one that always amazes me is Dover sole. Customers just can't get enough of it, but it's not, to my knowledge, ever been flagged up as an endangered species and it is regarded as an important and valuable food fish. We often serve cod's tongues and fish cheeks and they are popular and important menu items in our fish restaurants, Scott's and J Sheekey. You may think that we aren't helping the cause, but in fact we're using the bits that no one else wants.

For more information about sustainable fish, visit the Marine Conservation Society website. It's also worth noting that the people at Young's Seafood are really doing their bit to promote sustainability, making sure that their buyers source their products from properly managed fisheries around the world.

Fish 'collar' curry

Serves 4

I do like a fish head curry. When I worked at the Dorchester, the Bangladeshi kitchen porters in the hotels used to take all our fish heads for their staff meals and make delicious fish curry. We all love having nice, chunky fillets of fish on our plate, but what happens to the rest of the fish? There's a lot more meat left on the head of some of those larger species of fish. In you're wondering what the collar is, it's the back of the head where the gills are -- and it's a meaty, gelatinous bit of the fish that isn't really bony as such, but has more of a plate structure surrounded by flesh.

The kitchen porters would dissect the head, leaving the meaty bits on the bone and make a really simple curry out of it. Because the flesh on the cheeks and collar is quite meaty it stands up to a bit of rapid curry cooking and doesn't disintegrate in the same way that a fillet would.

Ask your fishmonger to save you the collars from large fish like cod and halibut.

1.5kg fish collars
Salt and pepper
60g ghee or vegetable oil
3 medium onions, peeled and roughly chopped
5 large cloves of garlic, peeled and crushed
1tbsp chopped root ginger
3 small, medium-strength chillis, seeded and finely chopped
1tsp cumin seeds
1/2tsp fenugreek seeds
1tsp cumin powder
1tsp freshly grated turmeric or 1tsp powder
1 pinch saffron strands
1tsp curry powder
Good pinch curry leaves
1/2tsp paprika
1tsp fennel seeds
1tsp mustard seeds
2tsp tomato purée
Half a lemon
1.3litre fish stock (a good cube will do)
3tbsp chopped coriander leaves

Season the pieces of fish with salt and pepper. Heat half of the ghee in a large, heavy-bottomed pan and fry the fish on a high heat until lightly coloured. Remove the fish with a slotted spoon and put to one side. Add the rest of the ghee to the pan and fry the onions, garlic, ginger and chilli for a few minutes until they begin to soften. Add all of the rest of the spices and continue cooking for a couple of minutes with a lid on to release the flavours, stirring every so often.

Add the tomato purée, lemon and stock, bring to the boil, season with salt and pepper and simmer for 45 minutes. Take a cupful of the sauce from the pan and blend in a liquidiser until smooth and pour it back into the sauce. Add the pieces of fish and simmer for 15 minutes then add the coriander and simmer for a further 5 minutes, seasoning with salt and pepper if necessary. Serve with basmati rice.

Home-smoked mackerel with beetroot and horseradish salad

Serves 4

Mackerel is a great fish and so versatile to cook with - and it's cheap (or should I say good value?). Forget the dyed fillets you buy vacuum-packed in supermarkets; you can buy delicious properly smoked stuff from a good fishmonger or smokery. I like to buy smoked fish such as mackerel on the bone; the fish is always more moist that way.

Smoking your own fish at home can be a rewarding experience. There are all sorts of smokers on the market these days, from the really basic ones where you light up the wood chips in a box to the smoker of all smokers that I saw in the Orvis fishing tackle shop in Bristol (01225 331 471) the other day. It was the size of a small domestic fridge with enough racks inside to smoke several sides of salmon, hot or cold smoked.

2 large fresh mackerel weighing about 400-450g each, or 2 whole smoked mackerel
Sea salt
Coarsely ground black pepper
Oak or other good quality wood chips

For the salad

2-3 medium beetroots weighing about 400g
A piece of fresh horseradish weighing about 70-80g, peeled and grated
2tbsp extra virgin rapeseed or olive oil
1tbsp cider vinegar
1tbsp chopped chives
2 lemons, halved

Season your mackerel well with salt and pepper and leave for about an hour. Prepare your smoker to hot smoke, according to the instructions, and smoke the fish for about 30 minutes and then leave to cool.

Meanwhile, boil the beetroots in their skins in boiling salted water for about an hour or until tender. Leave to cool, then remove the skin and cut the beetroot into rough 1cm dice. Mix the beetroot and horseradish together then add the vinegar, oil and season to taste. Then stir in the chives and season more if necessary. Remove the head from the mackerel (if it has been smoked with it on) and then chop the body in half through the bone. Serve the fish on plates with the beetroot and lemon and some good chunks of brown bread.

Fish bourride

Serves 4

Bourride is a kind bouillabaisse from the French Mediterranean. Fish such as gurnard, grey mullet, and huss are ideal for this dish, as they hold together well during cooking. Feel free to use any other fish that's available; and you could even use some chunks of lobster.

2 shallots, peeled and finely chopped
A good knob of butter
100ml white wine
150ml fish stock, made from fish bones
1 small clove of garlic, peeled and crushed
300g gurnard fillet, trimmed, pin bones removed
300g grey mullet fillet, scaled, pin bones removed
4 large dived scallops, cleaned - or you could use cod, skate or monkfish cheeks
300ml double cream
Salt and freshly ground black pepper
1tbsp chopped parsley

In a saucepan large enough to take all the fish, gently cook the shallots and garlic in the butter for 2-3 minutes without colouring. Add the wine and fish stock, then carefully place in the fish, bring to a gentle simmer and continue to simmer for a minute. Then carefully remove the fish with a slotted spoon on to a plate. Boil the cooking liquor until it has reduced by about half, then add the cream and continue to simmer gently until the sauce has reduced again by half and thickened. To serve, reheat the fish in the sauce for about a minute, season to taste and arrange on warmed plates with the sauce spooned over. Serve with mash, Jersey royals and greens such as steamed spinach.

Roast fillet of pollack with St George's mushrooms and agrette

Serves 4

Is pollack going to be the new cod? It certainly has the right credentials, especially when you take fillets off a large 4-5kg fish. Smaller fillets tend to be flaky, rather like whiting, so if you're going to serve it roasted, steamed or poached, then be sure to order fillets from a large fish.

If you have a good greengrocer then they should sell St George's mushrooms and agrette (monk's beard), an Italian green, chive-like vegetable that is great in salads, risottos or lightly cooked in fish dishes like this. Tony Booth in Borough market will certainly sell it, or you could try the Goods Shed in Canterbury (Station Road, Canterbury; 01227 459 153). If you can't get hold of agrette you could substitute it with baby leeks or samphire. If you know how to forage for mushrooms then you will most certainly know where to find them; but open cup or button mushrooms are also perfectly acceptable alternatives.

4 fillet portions of pollack from a large fish weighing about 200-220g each, skinned and bones removed
1tbsp plain flour
2tbsp vegetable oil
200g St George's mushrooms, cleaned and halved or quartered if necessary
2 shallots, peeled and finely chopped
A good knob of butter
100ml white wine
2tbsp crème fraîche
200g agrette, trimmed of its roots
Sea salt and freshly ground white pepper

Pre-heat the oven to 230C/gas mark 8. Season the fillets of pollack well with sea salt and white pepper and leave them to stand on a tray for about 10 minutes. Pat the fish dry with kitchen paper and lightly coat in flour, shaking any excess off. Heat a heavy-bottomed frying pan (preferably with an ovenproof handle) with the vegetable oil and quickly pan-fry the fish on a high heat for a couple of minutes on both sides, then finish cooking in the oven for about 6-7 minutes.

Meanwhile heat the butter in a heavy frying pan and cook the shallots and mushrooms on a medium heat for 3-4 minutes, stirring every so often. Season, add the wine and turn up the heat until the wine has almost entirely reduced. Then add the crème fraîche and agrette, and simmer for a couple of minutes, stirring the mushrooms and agrette until the sauce is just coating them, but not too thickly.

To serve, spoon the mushroom mixture on to warmed plates, placing the fish on top.