America's Newest Burger Kings

It's the icon of American food, that ubiquitous palm-size patty served between two slices of bread with a wedge of lettuce, square of cheddar and slice of tomato.

For years, it's survived under heat lamps, through take-out windows and onto sticky plastic trays. But, out of nowhere, the dining scene has changed. The American Burger is having a renaissance as gourmet restaurants are touting the sandwich. While a Carl's Jr. or McDonald's is probably near you, here are some of America's newest and hottest bourgeois burger joints.

BLT Burger, Las Vegas

What to order: American Kobe Burger

BLT Burger's old-fashioned booths

It's the second installment of Bistro Laurent Tourondel's BLT Burger, located in the Mirage Las Vegas. Among a hotel of foodie outposts and be-seen diners, it's one of the hottest late-night dining scenes in the city. It's open till 2 a.m. weekdays and 4 a.m. on weekends. The circular open kitchen allows dressed-up guests to watch while enjoying plasma-screen displays of sports events and hip-hop videos.

Thirsty guests descend on the BLT Burger Bar, which has more than 20 beers on tap, exotic cocktails and imported wines. An appetizer menu includes Kobe sliders, barbecued nachos topped with brisket, and homemade chili drizzled with crème fraiche. Burger variations include buffalo chicken, lamb tandoori and American Kobe served with Wagyu beef, and sides like Vidalia onion rings and sweet potato fries.

Radius, Boston

What to order: Radius Signature Burger

It's the perfect balance of grown-up restaurant and perky social lounge, with a post-office cocktail scene. But among the rolled-up sleeves and loosened ties of this Financial District-based French eatery by Michael Schlow is a burger that was feted as America's best at the 2008 South Beach Food and Wine Festival.