"I've rolled my eyes at some of the things we've asked them to do," Colicchio said. "But it's fair because all the contestants have to do it. And as you've seen, most of them rise to the challenge."

Deciding whom to ax from the show can take hours as the worried contestants sweat their fate in a space known as the Stew Room. "There have been times when it's 4 in the morning and we're tired and we'll keep going until we have a decision," Colicchio said. "I think that honesty comes through."

Growing and growing

With "Project Runway" now moved to Lifetime, "Top Chef" is king of the Bravo empire, and it continues to expand its influence.

In the book world, "Top Chef: The Cookbook" became a New York Times bestseller, and a follow-up, "Top Chef: The Quickfire Cookbook," will be released in October. Meanwhile, "Top Chef" branded chef knives, bouquets from Teleflora (some scented with cinnamon sticks and orange slices, others featuring a mix of flowers, fruit and vegetables) and a line of luxury wines are also on the way, as is a subscription-based online cooking class taught by past contestants.

A second edition of "Top Chef Masters" is being discussed, as is another spinoff, "Top Chef Juniors," in development at the network.

The show's alumni have capitalized on their newfound fame. Hall, the Season 2 winner, plans to open up his own restaurant, the Gorbals, in downtown L.A. this month. And this year's runner-up, Stefan Richter, will take over Santa Monica's L.A. Farm, which will be renamed Stefan's at L.A. Farm.

And "Top Chef's" inaugural winner, Harold Dieterle, opened his own place, Perilla, two years ago in New York City. There's still a wait to get in. (Later this year, viewers will be able to catch up with other past contestants with a special "Top Chef: Where Are They Now?")

The new season of "Top Chef" is set in Las Vegas and boasts the show's highest-caliber lineup yet. Among them: a Michelin star recipient, more than one James Beard Award nominee and several who have trained with world-class chefs.

"All I can tell you about Season 6 is that it's by far the best food we've had," Colicchio said. "I know you think I'm just saying that, but it was really, really good."