Three ways with mackerel: pan-fried, smoked and cured, with rhubarb puree, beetroot crisps and watercress oil

I cook with mackerel quite a lot, and regular readers will know that I have covered it in various guises in this blog before. However it has been a fair while since its last appearance, so it’s about time that this amazing fish is top of the page again. Every week that I write, in fact every time I cook, I learn something new, and I am constantly looking back on how to improve things that I have made before. My mind is always whirring away trying to work out flavour combinations or complete a long list of initial ideas that just require one or two things to tie them together. So I guess that this is an update on a mackerel and beetroot recipe that I posted last January, but slightly more refined and a damn sight prettier. 

 
We are now nearing the end of the mackerel season as they group up to spawn in the spring, but soon it’ll be summer again when there’s nothing better than flashing it on the barbeque with capers, lemon and parsley. Though the beauty is in its versatility, and as the year moves into Autumn it is just as comfortable with crunchy raw root vegetables or spicy broths, then back around to now where the season happily coincides with those new shoots of vibrant red rhubarb from the Yorkshire triangle. I am always so shocked at how bad the supermarkets are in reacting to British seasonality, and this vegetable is a fine example. Despite proper forced rhubarb only being around for a short few of months, I was saddened to still see thin and bendy imports lining the shelves. As usual, my local greengrocers knew better and I was soon walking home with a happy bunch poking out the top of my bag. Rhubarb is good for more than crumble alone (although buy extra for that too) and finely compliments savoury things like oily fish and pork. The key is in the balance, you want to keep the tartness or your main will think it’s a dessert.
   
I’m still amazed by how easy it is to hot smoke things at home. I was initially worried that my flat would be filled with clouds of black smoke, but even the crumbly old extraction and a few open windows miraculously contained everything in my tiny kitchen. So far I’ve only really tried it with fish that cook quickly using bungled smoke combinations of rice, herbs and zest, but the results really are great. The fish ends up meltingly moist with just the right amount of smokiness. Oh how I yearn to have a garden to expand on these projects…  

There are quite a few processes in this recipe but as with most things loads can be done in advance. It’s really up to you how far you take it, and the flavourings still work perfectly if you were to cook all of the mackerel just the one way. Likewise, I have perhaps been a little fancy in just using the loins of the fish here, but in no way were the trimmings wasted. Quickly grilled and crammed between soft white bread with tartar sauce they were delightful. But the whole fillets can also be used throughout this recipe too, especially if you wanted to bulk it out a bit.  

Serves 2 for a starter or light lunch.  

Ingredients:  

For the pan-fried mackerel:  

2 mackerel fillets, top loin only, pin boned 
Olive oil 
½ a lemon, juice only  

For the smoked mackerel:  

2 mackerel fillets, top loin only, pin boned 
Olive oil 
1 handful of rice 
1 lemon, zest only 
½ a bunch of thyme 
1tsp black peppercorns 
1tsp brown sugar  

For the cured mackerel:  

2 mackerel fillets, top loin only, pin boned 
100g salt 
50g caster sugar 
1 lemon, zest only 
2tbsp fresh thyme leaves  

For the rhubarb puree:  

1 large stick of rhubarb 
½ a lemon, juice only 
2 tbsp caster sugar, plus more to taste  

For the watercress oil:  

50g watercress 
100ml extra virgin olive oil  

For the beetroot crisps:   

1 golden beetroot 
Vegetable oil for frying, approx. 1ltr  

For the smoked beetroot salt:  

3tbsp smoked sea salt 
¼ of a beetroot, roughly chopped  

To finish:  

3tbsp cress, washed 


To cure the mackerel, mix together the salt, sugar, lemon zest and thyme. Pour a quarter of this mixture onto the bottom of a small dish or tray and top with the two mackerel loins. Cover with the rest of the salt mix until fully covered. Cover with cling film and refrigerate for two hours. 

While the mackerel is curing make the other elements of the dish. 

To make the smoked beetroot salt, pour the salt into a small bowl and add the chopped raw beetroot. Mix well and set aside, stirring occasionally. The longer it is left the more the salt will take on colour. 

For the rhubarb puree, chop the rhubarb into inch-sized pieces and tip into a small saucepan. Add the lemon juice and sugar and cover with water. Bring to the boil and then simmer for a couple of minutes until cooked through. Drain and transfer to a food processor and blitz well. Taste and add more sugar or lemon if needed, you want it to be quite tart still. Pass through a fine sieve into a bowl and set aside. 

Heat the deep frying oil in a heavy saucepan until it reaches 160⁰C. Peel the golden beetroot and carefully slice very thinly with a mandolin. When the oil has come to temperature, fry in small batches until lightly golden and crispy. Drain on kitchen paper and sprinkle with salt. 

For the watercress oil, put the watercress, extra virgin olive oil and a little salt into a food processor and blitz until the leaves are finely chopped and the oil has taken on a vivid green colour. Pass through a fine sieve and transfer to a bottle. 

When the mackerel has had its curing time, remove from the fridge and lift the fillets out of the salt. Rinse well and pat dry. Carefully slice the skin off and then set aside to come to room temperature. 

To make a DIY hot smoker, tip the rice, sugar, thyme, peppercorns and lemon zest into the bottom of a small deep metal oven tray that has been lined with foil. Start the smoking process off by singing everything with a blow torch. Place an oiled metal cooling rack or other grill on top and then seal with more foil. Put the tray over a medium heat until lots of smoke and heat is generated inside. Season the mackerel fillets and rub with oil. Peel back the foil and place the fillets skin-down onto the hot rack, then seal again quickly. Smoke for 4-5 minutes, or until just cooked through. Keep warm. 

Heat a non-stick frying pan with a little olive oil. Season the remaining mackerel fillets well. When a medium-hot temperature, add the fish skin-side down, holding them for a few seconds to stop any shrinkage. Fry for 2 minutes to crisp up the skin, then turn over and remove the pan from the heat and allow to residual heat to finish the cooking off. Squeeze over the lemon juice.

To plate up, lay one of each of the mackerel fillets onto heated plates. Dot the puree and the oil around the fish and scatter over the beetroot crisps and the cress. Finally sprinkle over some of the smoked salt.