Kelly Clarkson says stuffed mushrooms helped her sing live

Beyonce may have lip-synced her way though the national anthem during Barack Obama's swearing-in ceremony, but Kelly Clarkson says Italian food got her through the big day.

TMZ has the "exclusive" scoop that Kelly Clarkson dined on stuffed mushrooms, half-pound meatballs, spaghetti and other Italian delicacies at Washington, D.C.'s Buca di Beppo the Sunday night before her inauguration performance of "My Country, 'Tis of Thee."

"We loved having her dine with us!!" the restaurant said over Twitter Wednesday.

"@tmz: Kelly Clarkson -- Stuffed Mushrooms ... Key To Singing LIVE tmz.me/143FaSn" we loved having her dine with us!!

— Buca di Beppo (@bucadibeppo) January 23, 2013

The big meal didn't keep Clarkson from being nervous about inauguration day. "I was incredibly nervous and cold," the singer tweeted afterward.

Wow ....I was incredibly nervous and cold ha! I just wanna officially thank President Obama for opening for me haha! Just kidding :)

— Kelly Clarkson (@kelly_clarkson) January 21, 2013

Check out Clarkson's performance below: