literally thousands of feet above sea level — as host Padma Lakshmi and judges Tom Colicchio, Gail Simmons, and Graham Elliot head to Colorado for Top Chef’s new season.

Lakshmi tells EW that the new season’s location brought up some unexpected difficulties that really put her and the 15 cheftestants to the test. Simmons, who’s been a judge on the show since season 1, echoes the sentiment, saying that altitude “definitely changed the game.”

“For me, filming was a challenge, just to digest all the food because I had terrible altitude sickness,” says Lakshmi. “I’d been there before, I’d been to the Food & Wine festival, I’d been to Aspen several times, but I’d never been there with the show for that long.”

Not only did the altitude affect Lakshmi, but it also contributed to the show’s dynamic and overall difficulty. All the judges agree that cooking that high up is completely different than cooking at sea level — for example, Elliot says, “not everyone took that into consideration because water doesn’t boil at the same temperature and other key cooking things like that.”

But the location didn’t just affect the technical aspects of cooking. “I think what the big difference is that the last 10 seasons focused more on avant-garde cooking,” says Colicchio. “I think this season we don’t see much of that — we saw more home-style, more basic cooking, rustic cuisine, comfort food, which was interesting.”

“We’re out in the mountains, in the city, in like the really rich, ritzy part and also in Aspen at the Food & Wine festival,” Elliot adds. “You’re seeing all the challenges based around that — everything from cooking in the mountains with snow falling down on you to cooking for the Broncos at the stadium.”

Season 15 of Top Chef premieres on Bravo Thursday, Dec. 7 at 10 p.m. E.T.