Flay teamed up with the White House executive chef Cristeta "Cris" Comerford defeating seasoned expert chefs Emeril Lagasse and Mario Batali.
Flay said on "The Early Show" Monday, "It was a very tough battle. I watched it last night at home with my wife and I knew what happened and I was still really kind of (nervous)!."
Flay said he'd previously met Comerford when he cooked at the White House on Father's Day last year.
For the secret ingredient, first lady Michelle Obama opened up newly-planted White House garden to the chefs. But the ingredients weren't just laid out for them -- they had to dig out the fresh vegetables themselves.
Flay said, "It was terrific, because it really created lots of conversation about what the garden really means to the White House. And the first lady really got a chance to talk about her initiative, getting kids to eat better across the country."
Flay called the garden "fantastic."
In the challenge, Flay and Comerford used Japanese eggplant and sweet potatoes -- personally recommended by Michelle Obama -- for their winning dish.
Flay and Comerford defeated Lagasse and Batali by just five points.
Flay said, "It was a very, very close battle."