Ingredients for 4 people:
One kilo of veal book tripe, 100 g butter, 100 g grated Parmigiano Reggiano cheese, beef stock, one large onion, salt and pepper
Boil the tripe in plenty of salted water for approximately 2 hours, drain and cut into strips.
Finely slice the onion and fry in half the butter for a few minutes. Add all the tripe strips, add salt and pepper, mix well and leave to cook for around two hours, adding the stock from time to time. When cooked, stir in the remaining butter, layer the tripe and the grated cheese in a dish, add gravy if you wish, place in a hot oven for a few minutes and serve piping hot.