Fans first saw Underwood wear the halter-top dress during the Season 4 finale in May 2005. She rocked the look when Ryan Seacrest called out her name as the winner. Bo Bice was the runner-up. Underwood shared some insight on deciding to slip back into the memorable look for the latest “Idol” episode.

Carrie Underwood topped Bo Bice to win American Idol on May 28, 2005. Her debut single was "Inside Your Heaven," but "Jesus Take the Wheel" (released in October) would become her first No. 1 hit. Season 23 is Underwood's first year judging American Idol, and she's shown great willingness to get nostalgic.

Carrie Underwood, 42, went back to her “American Idol” roots for the season’s “iconic Idol moments” special on Monday night. For the occasion, the singer — who is now a judge for the singing competition show — chose the exact same dress she wore in 2005 when she won Season 4.