Angelini Osteria is almost everyone's favorite Italian restaurant in midtown: an informal room with well-designed trattoria cooking, a place to settle into for a plate of bombolotti or a Sunday saltimbocca, where whatever diet you happen to be on at the time will be accommodated without a fuss. Some nights, it feels as if everybody in the room knows one another, but you're in on the party too. You drink well, you eat well and you go home. A lot of chefs have come out of that kitchen, including Ori Menashe of Bestia. But while Gino Angelini, the owner and chef, is a genial presence in the osteria, bouncing from table to table in his trademark red skullcap when he is in the mood, a certain contingent of his customers has always wished that he had a bigger stage, especially after his restaurant La Terza closed a couple of years ago. Angelini, a native of Rimini on the Adriatic coast, was the last chef at Mauro Vincenti's Rex, the grandest restaurant ever to open in Los Angeles, and then at Vincenti, the brilliant Italian restaurant in Brentwood - he is capable of cooking at the very highest level. So lovers of Italian food were elated last year to hear that Angelini was planning to open RivaBella, an enormous restaurant in the former Hamburger Hamlet space on the west end of the Sunset Strip, a place where he might once again spin out his offal dishes and sauces thickened with vegetable purées, his delicate pastas and carefully undercooked squid. Could this finally be the alta cucina palace he deserved? Could it be the important restaurant the neighborhood has been missing since the shuttering of Spago and Le Dome? PHOTOS: Inside RivaBella RivaBella is certainly grand enough in its particulars, jutting onto Sunset like the prow of a great ship. Most of the restaurant is taken up by a patio, so soaring and extravagantly roofed that you may not notice that the circular booths and bare marble tables are outdoors until a small breeze cuts through the warm evening air and a waiter appears to switch on the heat lamps overhead. Another dining room, as big as many stand-alone restaurants, resembles a vaulted wine cave. Waiters glide by with lobsters and big slabs of Piedmontese beef. Fireworks erupt from birthday sweets, not mere candles but super-sparkler pyrotechnic displays. The wine flows like ... wine. There are occasional flashes of brilliance here - a softly sweet purée of carrots under the sautéed sea scallops, or a juicy, oregano-scented salmoriglio, kind of a Sicilian pico de gallo, spooned onto grilled branzino fillets - but this may be a different kind of cooking from what we've seen from Angelini before. So where his pasta with mint and lamb ragù at La Terza was vibrant but a little haphazard, like a dish Angelini had come up with on the spot, the chewiness and the tingle of fresh herbs in RivaBella's version is rather precise. Angelini has a way of making pastas in cream sauce seem light and almost refreshing - the tagliolini with basil and lemon, and the fragile asparagus-stuffed mezzalune with saffron taste vibrantly of spring. Even the slightly stodgy linguine with sea urchin, which lacks the briny intensity you might crave if you've tasted similar dishes at Osteria Mozza or Esca in New York, can be a perfect summer lunch dish if you have it with a crisp, cold glass of Vermentino. The theme here, if there is a theme, is probably the perfection of regular-guy Italian food, so that the seared swordfish carpaccio is sprinkled with bottarga, the chopped salad is enriched with quail eggs and the lasagna recipe comes from Angelini's grandmother, a crisp-topped square of layered pasta, long-cooked meat sauce and creamy béchamel. Eggplant parm comes out as a luscious eggplant timbale in a light Parmesan cream, garnished with a crunchy haystack of fried, shredded purple skin - like the kind you get in Queens, only more beautiful, and with probably half the oil. There is a vitello tonnato, of course, but the thin slices of cold roast veal are arranged as carefully as petals of sea bream on a sashimi plate, and the puréed tuna sauce snuggles into the contours of the meat like cream. RivaBella features not quite the personal alta cucina of Rex, the serenely businesslike cooking of Vincenti or the elevated trattoria cooking of Osteria Angelini, but a kind of Italian cuisine in a streamlined international style. The food is slick and professional - you're not going to be making many of these dishes at home - but also reproducible, a little too engineered, as if Angelini were already looking toward opening RivaBellas in Las Vegas, Scottsdale, Ariz., and Newport Beach. You want pizza? There's pizza, crunchy and very thin-crusted; a sublimely musky one with Gorgonzola and thinly sliced porcini, or a springtime pizza with burrata and squash blossoms. RivaBella, you begin to realize, is probably less Angelini's project than the newest outpost of the Innovative Dining Group, which is the company behind Sushi Roku, Boa Steakhouse and Katana, among others. All the IDG trademarks are here: sleek bar, soft but loungy music and sharp-suited managers who wander the floor, looking after VIPs. The vibe isn't obtrusive, but to people who care about these things, it is clear that you are not just eating dinner, you are In da Club. Italian favorite Gino Angelini finds a bigger stage, but is that necessarily better? 9201 W. Sunset Blvd., West Hollywood, (310) 278-2060, rivabellarestaurant.com Pizzas, $14-$27; antipasti, $10-$26; salads, $12-$22; pastas, $14-$22; main courses, $28-$40 11:30 a.m. to 2:30 p.m. Mondays to Fridays, 5:30-10:30 p.m. Sundays and Mondays, 5:30-11 p.m. Tuesdays and Wednesdays, 5:30 p.m.-midnight Thursdays to Saturdays. Credit cards accepted. Full bar. Valet parking. Pizza with Gorgonzola and porcini; mezzaluna pasta with asparagus; sea scallops with carrot purée; branzino with spinach and salmoriglio.