Answer:
This dish made of minced pigs liver, heart and lungs is a traditional English dish sometimes also called a savoury duck. However such preparations are common throughout western Europe wherever the pig and its offal was a peasant staple meat. A way of using those parts of the pig which if they were not used quickly they might spoil. The the ingredients listed above are all minced finely and the minced meats are formed into a ball, wrapped in caul (the mesentery membrane that lines the pigs abdomen) and baked in a hot oven until nicely browned and thoroughly cooked. Traditionally these are prepared by the local butcher and sold cold to be reheated at home. Very good with an onion gravy.
They are an old-fashioned British food, and one that has sadly fallen out of favour in recent years. However the rise of so-called nose to tail cuisine in some fashionable London restaurants , for example, St John, may see a revival in their fortunes.