Preparation :
Gut the mackerel. Wash well. In order to loosen the flesh do a squeeze-release motion with two fingers in an upward direction several times. In order to break the bones move it right and left exactly 1/4 inch over theri tails, then break the same bone also from right below their heads, then by holding the bone from its head part pull it out by moving ir right and left, now the fish bone is removed. Squeeze the fish gently in order to remove the flesh without tearing the skin, and remove the flesh from the tail to the head; leaving only the skin (to be stuffed afterwards). Ckeck the flesh for any small bones, then chop the flesh with a sharp knife. Put 1 glass olive oil and grated onions into a pan and saute until the color of the onions changes. Add ground walnuts, pine nuts, currants, cinnamon, black pepper, allspice, and a pinchof salt along with the chopped flesh into the pan. Cook over moderate heat for 5 minutes and stir. Just before removing the pan from the heat, add chopped parsley and dill. Stuff the fish while the filling is still hot. Flour both sides of the fish, roll in beaten egg, then roll in breadcrumbs or semolina and put in a frying pan in which th eolive oil has been heated beforehand. Fry both sides, remove from the frying pan and drain away excess oil. Allow the mackerel to cool and then put on a serving plate.