This is a particular favourite of ours discovered when living on Mallorca.
Frito Mallorquín is a traditional dish made from heart, lung, liver and kidney, usually of lamb but can be from any other animal - goat is particularly good. Small cubes of the meats to be used, potatoes, red peppers, onions and bulb fennel are fried in olive oil with salt, pepper, fresh fennel, bay leaf and pepper, but a little chilli makes it spectacular. It neesds to be eaten piping hot so heat bowls before serving, serve with bread and aiollí. This is probably arabic in origin and I have never seen it 'up North'. The Spanish make a great deal from offal and it is readily available in butchers, but we never find chicken with their giblets. Odd.