Haddock is a fish that deserves a bit more love. It’s a member of the cod family that, like cod itself, is one of those unfortunate fish that’s been in such high demand that it’s been overfished for decades. That said, the fisheries in the Nordic region are notably well managed, so fish from there is a really good option. Haddock grows quickly, too, so hopefully in future we’ll see an increase in the catch, so long as quotas are obeyed and the industry works hard on the way it’s fished.

Smoked haddock fritters with cheese sauce (pictured top)

Smoked haddock is a perfect fish for giving that lovely smoked flavour to a hearty dish of this kind. The fritters are simply delicious and will become a favourite once you’ve made them. I’ve also made them with both smoked mackerel and crab, so maybe try putting your own spin on this one.

Prep 15 min
Cook 1 hr 30 min
Serves 4

To serve
4 spring onions, trimmed and finely sliced
1 tsp sweet smoked paprika
50g parmesan, finely grated

Bring the milk and garlic to a simmer, then gently poach the chopped haddock for three minutes. Lift out the haddock pieces with a slotted spoon, then strain the poaching liquid and measure 250ml of it into another pan, leaving the garlic behind. Over a medium-low heat, stir the butter into the milk pan and, when it has melted, add the flour and stir until the mix comes together and looks like a smooth dough. Turn down the heat and cook, stirring occasionally, for five minutes.

Transfer the dough to a mixer or bowl, leave to cool for two minutes, then whisk in the beaten egg a little at a time, until it is all well incorporated. Fold in the haddock, cheese, parsley, mustard and spring onions, then season. Transfer to a container and refrigerate.

To make the sauce, warm the remaining milk in a saucepan. In a second pan, heat the butter and olive oil until the butter is melted and bubbling. Add the flour, cook, stirring, for two minutes, then stir in the warmed milk a ladleful at a time, until it is all incorporated. Bring to a simmer, then turn down the heat as low as possible and cook for 20 minutes, stirring occasionally to ensure the sauce doesn’t catch. Add the mustard, chives and cheese, and whisk until the cheese has melted and is fully combined. Taste, adjust the seasoning as required, and keep warm.

To cook the fritters, heat a deep-fat fryer to 180C (350F) or heat some sunflower oil in a deep, heavy-based pan (don’t fill it by more than two-thirds). Heat the oven to 120C (100C fan)/250F/gas ½. When the oil is hot, take a spoonful of the fritter mix, then, using two tablespoons, shape it into a rough rugby ball shape. Carefully drop the fritter into the hot oil and cook for three minutes, until golden. Working in batches of no more than six at a time, repeat with the remaining fritter mix. Drain the cooked fritters on a plate lined with kitchen towel, then keep warm in the low oven while you fry the rest of the fritters.

When all the fritters are cooked, gently reheat the sauce and share a few spoonfuls between four warmed plates. Top with the fritters, sprinkle over the spring onions, smoked paprika and grated parmesan, and serve hot.

Grilled haddock with braised leeks and anchoïade sauce

When you get good haddock, there’s nothing nicer than a simply grilled fillet: the blistered, almost burnt skin goes so well with the soft, sweet texture of the flesh. This dish is very quick to put together. Once you understand the technique of making a warm mayonnaise sauce, you’ll never look back. Anchoïade is traditionally a condiment used in Provence at the start of a meal, and it gave me the inspiration to make a version of my own. Combined with the haddock and leeks, it’s delicious.

Prep 10 min
Cook 25 min
Serves 4

2 tbsp sunflower oil
Sea salt and black pepper
4 120g haddock fillet portions, scaled and pin-boned
1 sprig fresh thyme, leaves picked, plus extra to finish

For the sauce
2 large egg yolks
1 garlic clove, peeled and chopped
8 anchovy fillets in olive oil
Juice of 1 lemon
250ml olive oil
2 tbsp double cream
4 tbsp fish stock
1 tbsp chopped chives

For the leeks
Olive oil
4 leeks, washed and cut into 3cm slices
Salt and black pepper
1 sprig fresh thyme, leaves picked
2 garlic cloves, peeled and crushed
100ml dry white wine
100ml fish stock

For the sauce, put the egg yolks, garlic, anchovies and lemon juice in a food processor and blend for 30 seconds. With the blades running, add the oil in a slow, steady stream, until the mix emulsifies, then season well and transfer to a pan. Stir in the cream and fish stock, then chill until you come to cook the fish.

Heat the grill to its highest setting. To cook the leeks, put a frying pan on a medium heat and, once hot, add a drizzle of oil. Lay in the leek slices and cook, turning occasionally, for three minutes, until golden brown. Season with salt, pepper and the thyme leaves, then add the garlic, pour in the wine and stock, and bring to a simmer. Cover and cook for eight minutes.

While the leeks are simmering, cook the fish. Oil and season a sturdy grill tray that won’t buckle under heat. Lay the fish skin side down on the oiled tray and season with salt, pepper and thyme. Brush with more oil, then flip over so it’s now skin side up. Slide under the grill and cook for five to six minutes, until the skin is crisp and the fish is just cooked through. Remove and leave to rest for two minutes.

Meanwhile, warm four plates in the residual heat of the oven, and gently heat the sauce, constantly stirring to the point when steam starts to rise from it. Do not let it boil!

Divide the leeks equally among the warmed plates. Stir the chives into the hot sauce, then drizzle it around the leeks. Top the leeks with a piece of haddock, scatter with more thyme leaves and serve.

Poached haddock and roast portobello mushroom rarebit

This is a lovely, comforting dish that would also work really well with most white or even smoked fish, especially smoked haddock. You can make the rarebit mix in advance and bake the mushrooms ahead, too, but it’s just as easy to make everything fresh. It’s also great for breakfast.

Prep 15 min
Cook 45 min
Serves 4

For the mushrooms
4 large portobello mushrooms, outer skins and stalks removed
1 shallot, peeled and chopped
1 sprig fresh thyme, leaves picked
A drizzle of olive oil
4 tsp white-wine vinegar
40g unsalted butter

To make the rarebit mix, put the butter in a saucepan and heat gently until melted. Add the flour, cook, stirring, for two minutes, then gradually pour in the cider, stirring all the time. Once all the cider has been incorporated, turn down the heat and cook for five minutes more. Stir in the cheese until melted, then add the Worcestershire sauce and mustard. Taste for seasoning, adding salt, cayenne pepper and thyme as required, and mix well.

Line an oven tray with baking paper and spread the rarebit mix on to it in an even, roughly 1cm-thick layer. Cover the surface with a second sheet of baking paper, to stop a skin forming, then leave to cool.

Heat the oven to 200C (180C fan)/390F/gas 6. Arrange the mushrooms upside down in a baking dish, sprinkle over the chopped shallot and thyme, then drizzle with olive oil and the vinegar. Place a knob of butter on each mushroom, then bake for 20 minutes. Remove and leave to cool.

To poach the haddock, put the milk, bay leaves, thyme and a pinch of salt in a wide pan and bring to a simmer. Carefully lay in the haddock, leave to poach for five minutes, then lift out the fish, transfer to a tray and leave until cool enough to handle.

Meanwhile, heat the grill to a medium setting. Flake all the fish and arrange it on top of the mushrooms. Cut out four circles of the set rarebit mix to the same diameter as the mushrooms, then lay one on top of each piece of fish to cover it. Season with black pepper, then grill for two to three minutes, until nicely coloured. Serve immediately, scattered with a few more fresh thyme leaves and perhaps with some dressed salad leaves on the side.

The Guardian aims to publish recipes for sustainable fish. Check ratings in your region: UK; Australia; US.

• These recipes are edited extracts from On Fish: A Seafood Handbook, by Nathan Outlaw, published by Kyle Books at £30. To order a copy for £27, go to guardianbookshop.com