Cut the tripe into squares of about 1 inch and
simmer it in a large pan of beef stock with the chunked
onion and celery for half an hour to an hour.  The cooking time
will depend on how pre-cooked the tripe is.  The tripe will
shrink some, but don't let it get soft.  Drain the tripe and keep
the stock.
     Chop and slowly fry the sliced onion in some olive oil
until it is well wilted, add the sausage cut in half and fry for
a bit longer. Now add the paprika, ancho chili powder and flour
and gently continue cooking for a while.  Add the tripe.
Add about a pint of the stock and keep it stirring around
until it boils and thickens. If you've misjudged the flour
thin it down with more stock. Add the nuts, most of the coriander, raisins, and salt and pepper at your discretion.

Cover the pan.  Allow the concoction to cook gently for
about an hour - keep checking that the tripe is not
sticking to the bottom of the pan. Towards the end check the
thickness of the sauce - if it's getting too thick
add some more stock and if it's too liquid remove the
lid and allow it to reduce. Serve the dish with some
fresh chopped coriander to make it pretty.