Cut the cooked Gras Double or ordinary tripe into large strips and shallow fry to a light brown colour in very hot lard. Season with salt and pepper and to each 1 kg (2¼ lb) tripe add 250 g (9 oz) sliced onion cooked to a light brown in butter. Mix together well and continue to fry together, tossing over and over until a nice brown colour.
Place into a deep dish or timbale; deglaze the pan with a little vinegar and sprinkle over the tripe. Finally, sprinkle with a little chopped parsley.