Mackerel with Mustard Sauce

I've eaten a lot of smoked mackerels, but never had a fresh piece in my hands. Until De Krat brought me one, or actually two fillets. Including a recipe, which I tried immediately as fish should be eaten as fresh as possible. What I particularly like about the dish is the crispy skin and the nice solid texture of the fish.

Preheat the oven at 250ْ  C, season 2 mackerel fillets, with skin, with some salt and black pepper. Create, in the middle of a baking dish, a mound of 1 chopped red onion, 1 bay leaf and a handful of fresh parsley (keep a bit aside for the garnish). Put the fillets on top with the skin side up, pour 100 ml of white wine over it and put in the oven. Cook for 7-10 minutes, depending on the thickness of the fillets. Put the fillets aside on a warm serving dish as soon as they're done, cover with some aluminum foil to keep warm.

Strain the cooking liquid from the baking dish in a small saucepan and boil for a couple of minutes to concentrate. Add 2 tbsp. of mustard and stir, whisk 30 gr of chopped cold butter through and let it simmer for about 3 minutes. Pour the sauce over the fish and garnish with some parsley.

Very nice with some skin cooked potatoes and a green salad. Very light, the fish is oily enough by itself.