‘Did you see him?” a customer at Convivio’s copper-topped bar whispered excitedly to her companion. “Mario just walked by.”

She was referring to Michael White, the chef of this newly reconfigured restaurant, who does bear a certain resemblance, in shape and coloring, to his fellow Italian chef. L’Impero, whose dark staidness sat easily in hushed, clubby Tudor City, closed in June, and reopened shortly afterward with the same chef but with a new name, bright Mediterranean colors, and a menu that emphasizes the vibrant south of Italy at slightly more accessible prices. The summer revamping was Mr. White’s attempt to create his own environment, more crowd-pleasing and festive than the one he inherited from L’Impero’s first chef, Scott Conant. The mistaken identity I overheard seems like a sign that it’s working: The Convivio diner, while hardly lacking in means or expectations, is a somewhat more casual, fun-seeking breed.

The mammoth one-page menu, printed in orange ink, tends to overwhelm. A few years ago, “middle courses” started appearing around town, shoehorning an additional $15 item into every meal. Convivio’s innovation is sfizi, “treats,” a few of which it is recommended each table start off with before proceeding to antipasti, then pasta, and then meat or fish. More courses is more European, to be sure — but in Europe, you don’t have to contend with such whopping portions. Diners who opt for the $59 choose-your-own four-course prix-fixe dinner get a good deal, but have a lot of eating to do.

The chef specializes in complicated, multi-ingredient modern concoctions, and robust, vigorous flavors, such as those of organ meats: Among a dozen antipasti can be found chicken liver, pig head, sweetbreads, and tripe, the latter exhibiting its chewy, dark savor in the context of a fat, delicious sausage ($12) that could be a meal on its own. Quail ($14), which excels in flavor but always provides a logistical hurdle to the eater, here is dealt a short, sharp skewer, and grilled in boneless pieces with pancetta, sweet onion, and vin cotto. A juicy-squab main course ($29) has so appealing a savory Sicilian bed of greens and sliced orange, with saffron, fennel, olives, and pistachio, that the bird could have been spared.

Pastas are central at Convivio, where the style is to cook them a little tougher than the usual. But plain ricotta dumplings ($19), however firm, taste great thrown together with brilliantly fresh peeled tomatoes, and a cast-iron casserole of cavatelli and coarse-cut goat meat ($23), broiled under a gooey sheet of mozzarella, is both comforting and overwhelming.

Mr. White has a conflicted relationship with seafood, the subtlety of which doesn’t quite hew to his big-flavors aesthetic. A bowl of stiff, ring-shaped pasta dotted with crumbled sweet sausage has a classic flavor, but tangled legs of cuttlefish puzzlingly tossed in contribute nothing but their chew. Raw sea urchin is one of the most interesting underwater tastes; cooked, as it is here in a dish of tough, oil-dressed gnocchi ($24), it loses all its marine tang and gains nothing but the grainy texture of overdone scrambled eggs. Rolling and stuffing fried swordfish filets ($28) is a neat idea, but with their sauce of creamy herbed yogurt, they take on the aspect of upscale fish fingers.

The excellently assembled wine book isn’t afraid to stray from Italy. Along with plenty of multi-hundred-dollar bottles to suit the restaurant’s grandeur, it offers a surprising number of sub-$40 choices to match the new accessibility. There’s also a larger collection of interesting Italian beers than I’ve ever seen.

It’s worth the effort to squeeze in dessert, if possible: the dense chocolate budino ($13), or just a choice of superb house-made gelato ($10).

Convivio, which still feels very new, makes a fine stage for Mr. White to show his colors in his own way. It retains the teeming staff of L’Impero, who, while not without their foibles, provide valuable, informed guidance through the intricacies and various pitfalls of the menu.

Convivio (45 Tudor City Place at 42nd Street, 212-599-5045).