Pound the meat slices gently, cut slightly into skin edges every 1.5 cm. Salt and pepper on both sides, dip into flour and fry quickly in the oil on high heat. Remove and keep warm. Pour drippings away, heat butter until it foams, boil down with the soup and pour over the served roast. Peel the onions and cut into rings, dust with a little flour, mix well and fry in a very hot oil until golden yellow. Remove, allow to drip off and then arrange the roast slices.