Chosen from Cook Simple by Diana Henry, she writes "It's a dish I first ate in Sweden, where they're fond of oily fish". This is a refreshing fresh mackerel recipe, best when the fish are freshly-caught that day.
Serves 4
8 mackerel fillets
Salt and pepper
45g (1½ oz) unsalted butter
125g (4½ oz) mushrooms, preferably a mixture of fresh wild ones and shiitake or oyster
A good squeeze of lemon juice
A small handful of flat-leaf parsley, finely chopped
Lemon wedges, to serve
Method
Season the mackerel on both sides and melt 15g (½ oz) of the butter in a non-stick frying pan. Fry the fillets, flesh-side down first, until golden, then carefully turn over and cook on the skin-side until crisp and golden. It will take about 3 minutes on each side to cook them through. Remove and keep warm while you quickly cook the mushrooms.
Cut any large mushrooms in half or quarters. Add the rest of the butter to the mackerel pan, turn the heat up and briskly sauté the mushrooms until they are golden. Add salt, pepper, a good squeeze of lemon and the parsley. Serve the mushrooms spooned over or beside the mackerel. Provide lemon wedges.

Diana says "If you can't get wild mushrooms, use cultivated field mushrooms rather than button mushrooms as they have a much better flavour. Cut the field mushrooms into slices about 5mm (¼ in) thick".