Recently, Lucas Hollweg wrote about a similar recipe in The Sunday Times style magazine. Soused Mackerel is a North European classic. "Sousing" means to pickle. I've used mackerel in this dish, but, typically, you could use any other oily fish such as herring ("maatjesharing" in Dutch or "matjes" in German and Swedish), and it might be an intriguing exercise to try the dish out with smoked haddock, instead. I think it would work.
In my version, I've used cider; as many of you will remember, I favour the use of cider in my cooking over white wine (it also gives this particular dish an added North European slant); but you could of course, use a dry white wine instead. The following recipe will serve four hungry people:
First, you'll need eight mackerel fillets. Living in central London, I bought my mackerel from the local supermarket and filleted them myself, as the so-called "fishmonger" behind the counter told me that he "hadn't been trained to fillet, had he?". I raise my eyes to heaven. Filleting is pretty straightforward, and would make a good subject for a future post. I managed to do a reasonable job- even without a proper filleting knife: our kitchen is currently in chaos.
Clean the mackerel fillets and arrange them in a flat dish. Sprinkle them with sea salt, and leave them for at least half an hour.
In the meantime, heat up your oven to 220C. Into a saucepan put: two thinly sliced red onions, one thinly sliced carrot, three cloves of peeled whole garlic, several sprigs of thyme, two bay leaves, two cloves, a small handful of black peppercorns, 500ml of a decent dry cider, and 120ml of cider or white wine vinegar. This will make your brine. Add 150ml of water and bring it to the boil. Simmer for ten minutes, add three small slithers of lemon peel, and simmer away for a five further minutes.
Wipe the surplus salt away from the fish, and pour over the hot liquor. Cook in the hot oven for up to nine minutes or so- until the fish is just about cooked through. Cool in the 'fridge and leave overnight. You will find that the red onions make the liquor go a subtle tinted rose-pink colour.
Check the seasoning, and serve cold with a generous amount of chopped parsley and hunks of warm bread to mop up the juice. If you're fussy about presentation, it might be an idea to remove the lemon peel and the cooked thyme (which will have gone a bit soggy and brown during the cooking), replacing it with a few fresh sprigs. Incidentally, I served my fish with the silvery skin of the mackerel intact; you could of course, remove this after cooking.
Ideal for a summer buffet in the garden.