Anyone who spends more than two weeks in Mexico becomes obsessed with the food. I've seen it happen over and over again. People arrive thinking it's the same stuff they get at Don Pablo's out by the mall-until they taste the real thing. Sometimes it's the perfect taco, sometimes it's a fancy classic like huachinango a la veracruzana-red snapper cooked with tomatoes, chiles and olives. That's when they know this is a pleasure they'll be pursuing for the rest of their lives.

People who study such things say Mexican cuisine is one of the five distinct cuisines of the world, the others being French, Chinese, Indian, and one I forget. These are the cuisines that all others stem from, the ones that have all sorts of theories and techniques and are so complex and varied that you can study them your whole life and still just scratch the surface.

I first discovered Mexican food at the age of 12, when my family moved to Mexico City. Kids that age are picky eaters, but I took to it immediately. It was like living in a parallel universe-all my favorites, like hamburgers and milkshakes, tasted awful in Mexico (as they still do). But they were quickly replaced by the most amazing tastes, like lime and cilantro and sauces of chiles. My 12-year-old prejudices disappeared completely, and I was soon eating fresh-caught fish with my fingers, fish seasoned only with lime and grilled by fishermen on an open fire on the beach in Puerto Vallarta.

And Mexican cuisine has something none of those other cuisines can offer, a built-in suspense factor. Will you get sick? The answer is, not as much as you used to, but it's still a distinct possibility. Never travel without Lomotil, the anti-diarrhea medicine that comes in tiny pills. And use common sense. I, for instance, never consume shredded lettuce, unpeeled tomatoes, strawberries, anything murky out of a jug, popsicles or milk. After a while you'll develop your own list, believe me.

But what should you do if you're going to Mexico for less than two weeks? What's the best way to experience this gastronomic treasure trove? Here's what I suggest from over 40 years of experience:

Have a good breakfast. Forget about the continental rolls in the hotel lobby and go out and get the real thing. Mexican breakfasts are great; somehow combining bacon and eggs with tortillas, cheese and salsa really works in a way you wouldn't expect. Try chilaquiles, for example-shredded chicken and tortillas with cheese and sour cream and salsa to taste, or scrambled eggs with chorizo sausages (like pepperoni but sharper and tastier).

One caveat, though. When Mexicans fry eggs, they really fry eggs. Chances are it will come out brown and rubbery around the edges no matter how hard you beg. But the bacon more than makes up for it. Mexican bacon is thicker, less greasy, more crumbly than American bacon. Mexican coffee is different, too. Stronger and more bitter, it seems to have a higher caffeine content. I wrote my first novel high on Mexican coffee. Two cups and you'll be climbing pyramids and racing through colonial churches all morning.

And the fresh fruit juice!

Lunch. The perfect place for lunch in a Mexican town is a nice simple restaurant facing the zocalo, or main square. You'll be looking out over a pretty park and the church, not to mention everybody in town passing by on their daily business. Order some sort of taco thing. At this point in the cultural life of America I certainly don't have to explain what a taco is, but I must say that a Mexican taco is infinitely more subtle and varied than an American one.

The taco, more than anything else, is Mexico's signature dish. It's what keeps the common man alive. It's cheap, easy to prepare, nutritious, filling and portable. Tacos are certainly easy to find. It seems that every block has two or three taquerias. And when there are no buildings around, somebody will set up a taqueria under a tent, heating up the tortillas over a fire in a steel drum. Add some folding card tables, a couple of benches, a very loud radio, and voilà, you're a restaurateur.

The taco has infinite variations and sub-variations, and the only filling I ever came across that I didn't really like was something involving a corn fungus. My own personal favorite is a simple combination of carnitas (little pieces of fried pork) and guacamole. I personally could live on guacamole and have very strong feelings about the subject; see adjoining recipe for what I consider the definitive version.

Dinner. You probably want to take a siesta before dinner, if for no other reason than to kill time. No Mexican would be caught dead in a restaurant before 9 p.m., and unless you want to dine in solitary splendor, you shouldn't either. I strongly suggest that for this meal you ask around and find some place special. Mexico has more than its share of what I think of as "fancy restaurants," and some of them are so good they are famous the world over, places like San Angel Inn in Mexico City and Las Mañanitas in Cuernavaca.

The ideal place would be like those: old, revered, with classic Mexican cuisine given a gourmet touch. I would suggest you try the chicken mole, with its unusual sauce of chiles and chocolate (it tastes like nothing else in the world and was invented back in the 1700s by a nun in Puebla with too much time on her hands; to cook it right takes three days), or chiles en nogada (stuffed chiles with a cream sauce containing walnuts and pomegranate seeds) or maybe some seafood (Mexico, believe it or not, has a longer coastline than the United States).

Hopefully, your restaurant will be in an old colonial building, half indoors and half out, with weathered columns and the sound of a fountain gurgling in the courtyard. The service will be impeccable. You will get just the tiniest bit drunk on your second cocktail. Then the mariachis come out.

I love mariachis but admit they do take a little getting used to. How much do you tip? What songs should you request? I solve the problem by always asking for an old chestnut called México, Lindo y Querido. It's the only one I know all the way through, and if you give me another drink I'll sing along. The chorus goes, roughly translated, "Mexico, beautiful and dear, if I die far away from you, just tell them I'm sleeping, and have them bring me to you."

And have some guacamole ready.

GUACAMOLE

2 ripe Haas avocados

1 half-inch slice of onion, chopped fine

1 lime

1 chile serrano (2 if you like)

1 tablespoon chopped cilantro

salt

Soak chopped onion in lime juice for 10 minutes. Mash avocados with a fork; add onion with lime juice, chile serrano and salt. If consistency is too thick, add a spoonful of sour cream. Add chopped cilantro.

Store in refrigerator with avocado seed in the mix and covered with plastic wrap until ready to serve. A nice way to serve is to sprinkle pomegranate seeds on top (make sure they are sweet). If you buy hard, unripe avocados, wrap them in newspaper (make sure the stem is not attached) so they will ripen more quickly.