Mackerel free from skin and bones, if you are using fillets, check for bones, mousse tastier without such surprises.

Into the processor put the fish, cottage cheese, sour cream, mustard, a bit of zest from the lemon and the juice of half a lemon. Grind to a smooth mass.

Add sliced chives, ground pepper, as needed salt or a little more lemon juice to Your discretion. Carefully whisk spatula, the mousse will be airy. Put in portions molds or in one large and put it in the refrigerator for 2 hours.

In the photo, the side dish consists of salad, red onion, lemon, pickled onion, cucumber and capers. And, of course, toast. But it can experiment, for example, to fill with mousse tartlets and serve with boiled eggs, tomatoes... Bon appetit!