Philadelphia is finally giving Mexican food the respect it deserves; at least, it's starting to. After all, transforming the city's collective perception of our southern neighbor's cuisine is bound to take a while. But the transformation has begun, and the Philadelphia food cognoscenti are reaping the rewards of the renewed attention this fabulously varied, deeply flavorful cuisine is getting.

The buzzword of the day is regionalism and this applies no less to Mexican food than it does to Italian, Indian or Chinese. As a result Philadelphians are, these days, experiencing at least some of the range of flavor, texture and overarching philosophy that regional Mexican cuisine has to offer.

Xochitl's menu is rooted in the cooking of Puebla, though there are side trips to other parts of the country. And while many of the dishes may seem familiar at first glance, executive chef Dionicio Jimenez's preparations almost always cast them in a far more nuanced light than most of us have experienced before.

Take the much-discussed guacamole con topopos, a riff on the standard made tableside. The dish is nothing terribly different from what you've probably had a million times before, at least in appearance. What sets Xochitl's version apart, though, is its exquisite sense of balance. I particularly enjoyed the bright notes of the lime juice, chopped onion and cilantro and the way they offset the richer, rounder flavors of the avocado. The weight and strength of both elements were in excellent harmony.

This same sense of balance also found its way into the ceviche, a generous portion of three deep-fried tortillas topped with a mix of citrus- and vinegar-cured octopus, shrimp and Spanish mackerel. In much the same way as the constituent components of the guacamole found a pitch-perfect harmony, the bright notes of the lime, infused vinegar, cilantro and jalapeno found their counterpart in the headier notes of the ripe tomatoes and avocados here. And in a truly miraculous turn of events, the texture of the octopus was spot-on--toothsome but not tough, tender but not spongy. (Anyone who's choked down under- or overcooked cephalopod knows what I'm talking about.)

Entrees, too, succeeded in much the same way. The chiles en nogada, a dish as traditionally Pueblan as any, yet sadly obscure on this side of the border, flirted with heat-but not too much-in a way that might be considered risky in any other context. But I have a feeling that Xochitl's guests are willing to give the kitchen a bit of leeway when it comes to these things.

This was a classic version of the dish, with walnuts, dried mango, papaya, apricot, pineapple, raisins and ground beef all stuffed inside a pleasantly spicy poblano pepper. The whole thing was draped in a velvety, creamy walnut sauce and garnished with toasted walnuts. Depending on the season either pomegranate seeds or syrup is used to anoint the dish and give it an added layer of complexity.

Like everything else I tasted there was a real sense of interplay here, of a delicate dance of bold flavors that was actually rather exciting. It could be a bit hot for some people, but for those of us who like the spice, it's a nice break from the bland norm.

Even the humble chicken breast got a sexy makeover and the pechuga de pollo was more subtly flavored than what most of us associate with Mexican cuisine and more European in appearance.

Here tender little discs of sliced chicken breast were presented simply on the plate, their centers filled with (among a number of other ingredients) garlic, onions, fresh corn and perhaps the most decadent ingredient of all, huitlacoche (a sinfully delicious corn fungus also affectionately called the Mexican truffle). And all of this was anchored by the crust of sesame seeds on the outside.

Just beware that, though they're brought to the table accompanied by a side of tortillas, they need no such help and are perfectly fine on their own. In fact, I tasted one of the pieces of chicken wrapped in the tortilla, and it was strangely diminished. Best to avoid the tortillas altogether with this dish.

As far as dessert, the churros y chocolate should be required eating for anyone with a sweet tooth--or even for those without one. The churros themselves are Platonic ideals of the standard (crunchy, light and fried to an exquisitely deep golden brown), but it's the sauces that stole the show: a classic chocolate enlivened with a bit of Mexican chocolate for a richer, more interesting flavor; and a cajeta (like a dolce de leche) with a bit of goat cheese folded in. With a cup of coffee, this is one of the best, simplest desserts in the city right now, a powerhouse preparation of such deceptive elegance that pastry chefs all over town should take notice.

The lesson, of course, is that you don't have to over-tinker with the classics when they're more than fine on their own--and when the chef and owner know exactly what they're doing (Marigold Kitchen's Steven Cook is the owner, along with Chef Jimenez). Xochitl seems to have gotten that lesson down pat, and Philadelphia is a tastier town for it.

408 S. Second St., 215.238.7280, www.xochitlphilly.com