Square 1682 combines substance and style

It is unlikely that William Penn would recognize a thing about Square 1682, the snazzy new hotel restaurant lounge at 17th and Sansom Streets named in his honor. Then again, I doubt many modern-day Philadelphians have seen anything quite like it in this city - a bilevel restaurant space with such a hyperkinetic sense of contemporary style, it would make most designer showrooms blush.

Devotees of the Kimpton chain, which created the new Palomar Hotel where Square 1682 resides, are familiar with the aesthetic, an über-fashionable hodge-podge of high-tech lights and funky modern art, living room-plush furniture in the dining room, glitzy balloon shades for window treatments, and eco-friendly cork on the ceiling. It's a lot to take in from the moment you step inside the revolving door: nattily-dressed cocktailians sip maple-infused Manhattans in the lively ground-floor lounge (with a square bar, naturally) beside the bustling open kitchen, while a floating staircase to the side winds up and around to the more intimate, 48-seat dining room upstairs.

I wasn't sure if I liked these rooms on my first visit, a sunlit lunch where the cork ceiling and bric-a-brac décor looked like an overdecorated plywood box. But it grew on me quickly over the course of two dinners. Long-armed lamps cast a golden light across the cushy central banquette lined with dating young diners, lending the room a special-occasion buzz. A modern stained-glass wall, meanwhile, illuminated a clever contemporary echo to the classic stained-glass windows of the First Baptist Church across the street. Though it is so self-consciously stylized, this restaurant still manages to connect like a snug puzzle-piece into the intimate and quirky urban setting that is Sansom Street.

I have many of the same feelings about chef Guillermo Tellez's ambitious menu, which has grown on me steadily over three visits. A globe-hopping New American swoop from Mexico through Asia and the Mediterranean, with stops in Chester County for heirloom veggies, his beautifully crafted plates were at turns artful and fun, but also, occasionally, overreached.

Usually, those stumbles were over small details in execution - too much citric tang on the truffled popcorn, not enough lobster in the lunch quesadilla, too much fat left on the lamb short ribs, an extra shine on the house-fried purple potato chips, or a flicker of too much ancho chile heat in the South American shrimp.

But those little slips became noticeably less frequent with each subsequent visit. And for the most part, my meals reflected the sophisticated eye and creative ebullience of Tellez himself, 45, a goateed Chicagoan who spent 18 years as a Charlie Trotter protege before landing in Philly to steward Striped Bass into its final days.

Exposed to both classic techniques and a world of flavors through travels with his former mentor, not to mention his own Mexican heritage, Tellez is just as likely to serve a hearty duck cassoulet (loosely inspired by a meal with Roger Vergé) as he is a ginger-braised short-rib cake with potato-wrapped seared tuna loin (a nod to Alan Wong in Hawaii) as he is a meat-and-fruit-stuffed poblano pepper en nogada, sauced with walnut cream and pomegranate seeds, like his Michoacana mother used to make.

From the Mediterranean, he paired reasonably tender tubes of charred octopus with lemony raw artichokes. Bacalao brought a notably airy brandade cake of mashed potatoes and salt cod over a garlicky schmear of slow-roasted tomatoes. The simple Spanish classic of pan con tomate is stylishly recast in flavorful miniature, with chewy crouton cubes over saffron tomato sauce topped with melting manchego and a bundle of silky Serrano ham.

Some of his international associations are rather loosely drawn, such as the "Korean" hot pot, which is really more Vietnamese and Japanese, its clear broth braced with lemongrass and dark soy before it's poured dramatically tableside over a raft of crispy soba noodles topped with crawfish tails, edamame, and gochujang chile-glazed monkfish. When it's this tasty, though, artistic license is excused.

If there is one unifying thread through Tellez's palate, it is his vivid use of spice for flavor more than heat. Chiles and avocado bits jazz a yogurt raita sauce that accompanies a gorgeous shrimp cocktail poached with kaffir lime curry. Rusty, rich guajillo sauce and pineapple salsa give a tropical "al pastor" flair to the lobster tacos (a more satisfying successor to those quesadillas). An Asian chile paste lends earthy heat to a barbecue sauce that slicks the tender lamb short ribs on the bar menu. A slow-roasted shred of pork carnitas, meanwhile, adds a savory Mexican accent to the seared black cod over creamy polenta.

There are, to be sure, several more subtly flavored dishes for less adventurous diners - albeit always with a colorful culinary twist. Meat-and-potato fans will find a beautiful local strip steak with a gratin of blue potatoes. For the chicken crowd, a roasted Amish beauty comes with creamy pink alfredo nest of pasta made from lightly pickled beets. Simply seared black bass comes with crisply fried eggplant and a risotto cooked with black rice. Seared grouper, meanwhile, arrives over mashed white sweet potatoes with a truffled puree of roasted corn.

These dishes were satisfying, if not necessarily profound, but spoke to Square 1682's mission as a hotel restaurant to serve a clientele of broad tastes and needs as stylishly as possible.

There are some fantastically arty boardrooms upstairs for small private events overlooking 17th Street. The downstairs lounge, meanwhile, could become a casual destination on its own for a fun bar-menu nibble (fried maitakes; yakitori; bacon-wrapped goat cheese-stuffed dates) and a seriously stocked craft cocktail bar within view of the lobby fireplace.

The service staff, while still at times awkward and out-of-sync (delivering wines too long after food was served), also had moments of genuine charm and grace.

The dessert menu, at least, was fine enough to bring our meals nicely full-square. There was a decadently creamy ginger-chocolate tart with candied oranges, and a martini glass filled with silky panna cotta topped with brûléed blood oranges and a tart pomegranate drizzle.

My favorite, though, were the moist sugar-rolled apple fritters in cider caramel. They harked back to Tellez's brief but memorable stint (post-Striped Bass) cooking farm-market tasting meals and barbecue at Northbrook Orchards in Chester County. These rustic Pennsylvania beauties, William Penn might actually recognize.