In saucepan put finely chopped onions, diced carrot, parsley, sliced ​​mushrooms and sauté them with a little water. Oven preheated to 180C. Mackerel are cleared, the pendulum tail and head are cut as fillets. In tray make first stewed products, put them on mackerel fillets and top rank rings of sliced ​​tomatoes. Watered with olive oil, seasoned with black pepper, add 1/3 cup water and bake for 30-40 minutes. In portion plate put fresh salad leaf and placed it on a piece of mackerel, together with the resulting mixture in baking.