For a more simple flavor, you can order Poc Chuc, which a pork loin that has been barbecued. Some chefs splash some achiote on it to give it a nice twist.
If you are very adventurous and like spicy food, take a bite of a habanero chile. If it is too much for you, DO NOT drink water, it only spreads the spice around and makes it even worse!! The locals recommend taking a pinch of salt and placing it underneath your tongue. They recommend this after they stop laughing and giggling at you sweating and crying your eyes out (I did not find it funny AT ALL!!!!!)