Boil the lamb pluck in salt water and cut into pieces. Fry the finely chopped onions in butter and some water. Add the rice, pluck, pepper and mint. Add 2 cupfuls of the lamb stock and boil some 20min. Soak the caul in cold water, cut into pieces and fill with the mixture. Arrange in a tray and bake in a moderate oven. When nearly ready, pour over the eggs beaten in yogurt and bake for another 10-15 min. The dish can also be prepared without caul wrapping. Serve with yogurt topping.