I just heard this one here in Spain:

An American tourist goes into a restaurant in Spain and orders the specialty of the house. When his dinner arrives, he asks the waiter what it is.
"These, senor," replied the waiter in broken English, "are the arms of the bull killed in the ring today."
The tourist swallowed hard but tasted the dish and thought it was delicious. So he comes back the next evening and orders the same item. When it is served, he says to the waiter, "These arms... are much smaller than the ones I had last night."
"Yes, senor," replied the waiter, "You see...the bull, he does not always lose."

cheers Jochen