Chicken dish at Penne. (Vicki Valerio / Inquirer)

The Inn at Penn gets it right the second time with a spot where the diminutive pasta chef stands tall.

Failed restaurant spaces rarely succeed in reinventing themselves.

The University of Pennsylvania's high-end hotel, the Inn at Penn, seems to have done just that three years after opening its disappointing Ivy Grille to a loud chorus of raspberries. But it took more than a new manager and kitchen staff to turn heads that way again.

Manager Harry Kratz, a veteran of the nearby White Dog Cafe, Restaurant Taquet in Wayne, and Jean Pierre's (now closed) in Newtown, had to endure nearly a year under the tattered Ivy flag while this bright, modern room was being reconceived behind the scenes. When it was finally relaunched last summer as Penne, a new restaurant had indeed been born.

It was worth the second labor. The hotel now has a flagship dining room worthy of the vibrant University City redevelopment project it anchors.

The space itself is not so different from its earlier incarnation. It still has a sunny wall of windows that looks out onto Walnut Street, a bright-yellow tin ceiling with whirling fans, and an open kitchen shaded by an amorphous modern, stainless-steel awning.

But it has taken on a certain Roman warmth, from the patchwork of ocher wallpaper panels to the deep-blue accents, gold carpeting, and the display of busts depicting Hercules, Mercury and other gods, replicas of sculptures from the University of Pennsylvania's Museum of Anthropology and Archaeology.

More important, Kratz has assembled a restaurant with real assets, including an extensive wine bar, young but diligent and friendly servers, and a modern Italian menu that stands on its own feet.

So what if the diminutive pasta chef, Roberta Adamo, needs a step stool to stand above the long terrazzo pasta bar, front and center before the open kitchen? She is easily the biggest attraction here, a nimble-fingered muse presiding over her domain of multicolored doughs x97 rolling, pinching and snipping away at the delicate noodle sheets, transforming them, in a puff of flour, into some of the most artful and original pastas in town.

I have begun to long for cooler weather again just so I can taste her beguiling strands of whole-wheat fettuccine tossed in garlicky butter with bitter brussels sprouts, fried pancetta, and tiny potato cubes.

But the warm weather has brought some lovely spring pastas, too. The wings of butterfly-shaped farfalle cradle tender fava beans and snappy slivered almonds with a sprightly yellow-tomato sauce emboldened with fresh mint. Little poufs of gnocchi x97 airy, yet firmed with a dose of polenta x97 float alongside dabs of melted mozzarella in a tomato sauce that is both ebullient and light.

For her oversized sacchetti, Adamo needs a dough that is strong but fine, so she makes it with egg yolks and white wine, which is lighter than water. The pasta is then tied into an elegant purse filled with nuggets of lobster suspended in a lemony cloud of artichoke-potato puree.

Her garganelli are my absolute favorite pasta here, an artisan's fluted penne with floppy, plumelike ends. They offer sheer delicacy and what Adamo calls "bitey" firmness, a combination that is the hallmark of handmade pasta. Cloaked in asparagus pesto with pine nuts and sun-dried tomatoes, they were so good that I could almost ignore the large undercooked shrimp that crowned the dish on two occasions.

Penne is more than a pasta boutique. It has one of the more intriguing Italian wine lists around, with more than 100 varieties to choose from. There are also 45 wines by the glass, which can also be ordered in a flight of three small pours of related wines (for example, three southern Italian whites).

There are several affordable options by the bottle, even though markups are steep. Yet, it's tempting to splurge on a glass of some of the finer wines without committing to a whole bottle, be it an intense red Brunello di Montalcino or one of my new favorite whites, the exotic and mildly spicy Fiano di Avellino.

The modern Italian menu from chef Ed Vadden (formerly of Brasserie Perrier and the Ritz-Carlton Philadelphia) is usually interesting enough to work with these sophisticated wines. But it is rarely as inspired as when he collaborates with Adamo, adding a sauce or garnish to one of her pastas. (Understandably, the two happily share the restaurant's top billing.)

The assorted appetizers are particularly weak except for a generous antipasto of good cured meats and pickled and roasted vegetables. A special cream of cauliflower soup was another highlight.

At lunchtime, there is also an assortment of excellent thin-crusted pizzas, including a delicious porcini-infused flatbread topped with truffled potatoes and goat cheese.

A few of the dinner entrees were lacking. The grilled salmon over purple potatoes was bland and underseasoned. The big pork chop just missed both times we ordered it: overcooked the first time, perfectly cooked on the second try but mismatched with a mushroom cream sauce.

A fillet of striped bass with lentils and greens was seared to such a thick brown crust that I couldn't slice through it without demolishing the fish.

But more often, Vadden's kitchen delivered interesting fare, carefully prepared to highlight good ingredients. A marvelous grilled sirloin was the epitome of indulgence, dripping beefy juices into a creamy Gorgonzola-scented polenta.

A pristine fillet of white halibut played against herb-roasted fingerling potatoes and a tomatoey puttanesca sauce piquant with anchovies. A nice red-snapper special also benefited from a spicy tomato sauce, this one jeweled with morsels of lobster and a nest of Adamo's delicate herb-flecked linguine.

Even a simple chicken dish was memorable, the breast of a Canadian bird roasted to crisp-skinned succulence and served with garlic whipped potatoes and rich brown jus.

Few of the desserts are made in-house, a letdown given the effort shown throughout the rest of the meal. Then again, Penne could do worse than showcase the delights of some good local pastry shops, such as Miel Patisserie's wonderful Piedmont (a light chocolate mousse over crunchy dark chocolate-hazelnut praline) and its sublime chocolate-glazed bombe filled with chocolate mousse and Bavarian cream. But the weirdly shredded apple-walnut tart disappointed, as did the rubbery lemon cheesecake.

Perhaps the best dessert came from Adamo, who is as adept at crafting cannoli shells as she is at turning pasta. The delicate tubes crumbled with crisp precision with each gentle bite, mingling the crunchy pastry with creamy clouds of their sweet ricotta centers.

With more flavors like that, this is one restaurant that doesn't need a third chance to get it right.

Contact Craig LaBan at 215-854-2682 or claban@phillynews.com.