How to make
Clean the mackerel and cut it into pieces. Put the pieces in a greased tray. Chop the celery and onion and sauté them in the remaining oil.
When tender, sprinkle them with flour and stir, until it fries as well. Top with some hot water to get a medium-thick sauce. Season with the spices and bring to a boil. Pour the sauce over the mackerel, arrange tomato slices on top, and between them, some thin slices of lemon.
Sprinkle the dish with chopped parsley and put it to brown in a moderately preheated oven.