Audiences know Kara DioGuardi best as a former judge on American Idol and TV songwriting competiton Platinum Hit, but DioGuardi is currently proving she's got some serious performance skills of her own as she makes her Broadway debut in Chicago. On September 6, the performer was greeted with roaring applause as the curtain came down on her first show as Roxie Hart in the long-running revival. Broadway.com was on hand to snap some photos of DioGuardi's exciting night. Click on to take a look!