Not sure if this one's been told yet/recently...

A tourist is on vacation in Pomplona, just in time for the "running of the bulls". As he strolls through the city, admiring the architecture, he spots a corner café and sits down for what he hopes will be a traditional Spanish meal. Perusing the menu, he spots a dish that sounds delicious and orders it. As he's waiting for his meal to arrive, he catches an intoxicating scent wafting over from a nearby table. Motioning to his waiter, he asks "what did that man order? It smells delicious!"

"Ahh senor, that is the fried cajones of today's bull. When the runners win, the bull is slaughtered and the cajones are considered a delicacy."
"Well that just smells great, I'd like to change my order to that," the tourist says.
"Impossible," says the waiter, "we are all out for today. Supplies go quickly."

Disappointed, the tourist eats his meal once it arrives, pays, and leaves. The following day, he returns to the same café and boldly orders the fried cajones. "Oh no, senor, you don't want that," the waiter warns. But the tourist is quite insistent and orders the cajones. As the meal arrives, the tourist eats them, motions to the waiter and complains about the taste. "This doesn't smell or taste like they did yesterday, what happened?"

"Well senor," the waiter says, "sometimes the bull wins".