What is authentic Mexican cuisine? Ancient dishes like bírria, menudo, and chochinita pibil are the easiest to categorize as authentic because of their age, but what about  colonial dishes like chiles en nogada or mole poblano?  Tacos al pastor and tacos de pescado were brought to Mexico even more recently by Lebanese and Japanese immigrants. Are these dishes still "Mexican?" The more recent the dish, the trickier it becomes to call it authentic. Unless of course, we agree that Mexican cuisine is constantly evolving with new dishes being created all the time. In this sense, Pujol has evolved significantly since my first visit in 2010. It is now not only a restaurant that recreates ancient dishes, but a restaurant that pushes Mexican cuisine forward by creating new ones. In the beginning Pujol looked inward at Mexico's rich culinary history, cataloging, studying, and improving upon very old dishes. Pujol still does this but with more confidence, now looking outward as well, placing one of the oldest cuisines into the context of international dining.

Enrique Olvera's cuisine is humble; you'll be hard-pressed to find caviar or foie gras at Pujol, let alone at local fondas throughout the country. I've never seen black truffle on the menu although huitlacoche, the mushroom that grows inside corn kernels south of the border, is in abundance. Chef Olvera's cuisine is local, and that's likely unintentional: that's just how things are done in Mexico.

Full disclosure: Having enjoyed Chef Olvera's food tremendously, I have since been to Pujol nearly twenty times over the past few years, and have come to know him on a personal level. I haven't seen a bill for my last four meals. After awhile, I suppose Chef Olvera began to wonder why the same pale gringo with a camera kept coming back. The answer is simple: Pujol is one of the most interesting restaurants in the world.

Though the menu changes several times a year, one course that has been served each time I've visited is a hollowed out gourd of elotitos tatemados con mayonesa de café y polvo de chicatana, smoked baby corn with coffee mayonnaise dusted in salty ant powder. The subtle acidity from a splash of lime lifts the creamy mayonnaise, while the smoke and ant powder contribute an addictive umami to the otherwise meatless dish. This snack is a tribute to the Mexican street vendors selling corn until the late hours of night.

As the restaurant evolves, simple deconstructions like a quesadilla in a shot glass (2010) are being replaced with more original flavor combinations based on Mexican fundamentals. Take for instance Chef Olvera's pescado del día en ceniza de cebolla, a lightly seared filet of snook dusted in onion ashes served with a nutty green mole. The green mole lacks any sweetness whatsoever, so the flavor is of pumpkin seeds and savory herbs. What's fascinating is how the charred onion layer concentrates the flavor of the green mole adding a subtle bitterness, much like how a burnt tortilla tempers a Pueblan or Oaxacan mole's sweetness. A single thin slice of serrano pepper adds an additional element of spice. This dish rests inside a sweet white onion layer and is eaten with the hands. It would be difficult to think of a more balanced dish.

A staple of Chef Olvera's cooking has been take a regional street food, study its flavors in depth, and enhance them. This is more than a cosmetic change, e.g., serving a taco on a plate: you won't be able to find this ingredient quality and attention to flavor elsewhere.

Sopes, a street food from Culiacán, Sinaloa, are ovular sheets of grilled masa traditionally topped with meat, fresh cheese, and acidified cream. In his sope de erizo, Chef Olvera takes this traditional street food and substitues the meat and cream with a thick layer of floral and creamy Ensenada sea urchin roe, brightened with a thin slice of raw onion. The urchin is lightly torched, mimicking the flavor of masa toasted on the comal.

Barbacoa tacos, a central Mexican dish of sheep slow-roasted in deep pits underground, is enhanced at Pujol with an avocado cream, spicy serrano chiles, and a poblano pepper tortilla. The sheep is very carefully slow-roasted for 24-hours producing a succulent, concentrated cut of meat. This is a dish that frankly, is tastier than any street version I've had.

If Mexico City had an official dish it would likely be tacos al pastor, the Mexican version of doner kebab kicked up with pineapple and cilantro. Served on rotating spits throughout the city, sheets of pork and pineapple are shaved off in one fell swoop into a corn tortilla. It's a heavy dish in which the tortillas are sometimes dragged through a layer of dripping pork fat before stuffed with pork. Chef Olvera's version is clean and lacks visible oil, where pork is replaced with snook.

One of the unique qualities of Mexico is its abundance of unique fruits, vegetables, and herbs that don't grow elsewhere. To showcase Mexico's produce, Chef Olvera creates his versions of the Gargouillou. The difference is, unless you're familiar with Mexican cuisine, you probably haven't heard of many of the ingredients.

La Milpa, literally translated as "the cornfields," is the place where the vegetable foundation of Mexican cuisine begins. " Chef Olvera pays tribute with a wooden slab holding colorful local squash, zucchini blossom, jumiles, pipicha oil, and small tomatoes. Binding the dish together are puréed beans and fresh cheese.

In a minimalist version of the garden dish, ensalada de nopales, Chef Olvera explores acidity and herbal freshness coming from the nopal cactus (served fresh and dehydrated) sweetened with green pea shoots.

Even heavy dishes, such as the Yucatecan bald pig in a pork reduction with bean salsa, are well-balanced in the context of the rest of the meal -- rare to find a meat course that doesn't weigh you down elsewhere. The pork fat contrasts against the splash of lime in the pork reduction and the spice of the yellow chile.

A meal at Pujol is a culinary tour of Mexican cooking with Chef Olvera as your guide. Some of the courses are hundred year old dishes brought up to date, others are creations using Mexico's ingredients and techniques as a foundation for creating something new.

Mexican cuisine is incredibly regionalized; it's difficult to find a restaurant that serves fine dining pan-Mexican cuisine without sacrificing quality. There are only a few restaurants that do this. (Two that come to mind in the U.S. are Topolobampo in Chicago, and lately Gran Eléctrica in Brooklyn.) Pujol is one of these restaurants, showing each region of Mexico at its best.

Having trained at the Culinary Institute of America, Chef Olvera also has the outside perspective of his country's cuisine that is necessary to make it approachable to the rest of the world. He has a unique ability to summarize Mexican cuisine in a handful of courses so that the meal is enjoyed by locals and foreigners alike.

Mexico is a country whose food is often neglected, partly because of the lack of modern chefs creating new dishes and pushing it forward. Enrique Olvera is bringing this cuisine to the international spotlight where it rightfully belongs.