For one thing, ingredients are often exotic, like nopales, fleshy pads of cactus, or cajeta, a sweet caramel flavoring made from goat's milk. Menu items can be unusual, too: squash flowers, chapulines (grasshoppers), gusanos de maguey (worms) fried and served with guacamole. And street food comes in every imaginable form, including some choices that will challenge the most adventurous palate (tacos featuring meats like beef tongue or pig snouts).
If you're looking for a traditional fine-dining experience—with prices to match—the dependable choices are in the big, expensive hotels along Paseo de la Reforma or in the Polanco neighborhood north of Chapultepec Park. You'll likely need reservations, and jackets are suggested for men.
The Mexican chains Vips and Sanborns have locations throughout the city and are good for a casual meal. Another casual alternative is the taco stands found on almost every street corner. Tacos al pastor, shreds of roast pork, grilled onions and cilantro heaped on a small tortilla, cost around 15 pesos apiece and are a popular late-night snack.
The El Globo bakery chain, with locations throughout Mexico, offers good-quality breads and pastries at low prices. For the homesick there are plenty of American fast-food outlets, including Burger King, McDonald's, Pizza Hut and Subway.
Reservations are needed for trendy and popular restaurants in the Polanco, Zona Rosa, Condesa and Roma neighborhoods. Another cluster of good restaurants and cozy sidewalk cafes are in the southern suburbs of San Angel and Coyoacán. Casual, family-style places are the rule in the vicinity of the Zócalo. Many restaurants close on Sunday.
Approach cocktails and liquors with caution if you are not used to the altitude. Also be aware that imported wines and spirits are heavily taxed; Mexican beers and wines are much less expensive. Although the better restaurants typically use purified water, avoid green salads, unpeeled raw vegetables and unpeeled fruit if you have a sensitive stomach. To be completely safe order drinks without ice cubes, or drink bottled water.
Restaurants often cater to the local custom of eating the main meal of the day in the early afternoon, then a lighter supper around 9 p.m. or later. Most begin to serve breakfast around 7:30 a.m., comida (lunch) about 1 p.m. and dinner after 7:30 p.m. From 2 to 4, restaurants can be crowded with a lingering lunch crowd; if you eat dinner before 9 p.m., on the other hand, you might have the place to yourself.
Don't expect every server to be fluent in English. A knowledge of basic Spanish or a handy phrase book not only helps in communication but also in deciphering menus.