Tripe and onions are one of those recipes that haven't been popular for many years. It has had a bad press but is experiencing a resurgence among foodies as it is low in calories and high in protein.
Cut the tripe into bit-size pieces and put in a saucepan with the onions, milk and water
Bring to the boil, then cover and simmer gently for 1 hour or until the tripe is tender
Mix the butter and flour together and, when all the flour is absorbed by the butter, break into small pieces and put into the tripe, stirring all the time until the liquid thickens
Transfer the mix to an ovenproof dish and bake in a hot oven for 30 minutes
Sprinkle cheese over the top and brown this, either in the oven, or under a hot grill.