Kelly Clarkson closed out The Late Show with David Letterman last night with her new single, “Already Gone” (which also serves as the “female farewell” for this season of So You Think You Can Dance).

If you’ve ever doubted the girl can sing, a pox upon your house. And while Clarkson can definitely belt with the best of ’em, the measure of a real singer is their ability to dig deep into the soul of a song and deliver those emotions honestly. Of course it probably helps that Clarkson had a hand in writing “Already Gone” (with OneRepublic’s Ryan Tedder).

On her album All I Ever Wanted, “Already Gone” is a little overproduced (curse you, Tedder), but singing it live on Letterman, Clarkson delivered a knockout performance that bests the album version. No idea what the DJ is doing on stage behind her, though:

Purchase Kelly Clarkson – “Already Gone” via iTunes, Amazon MP3.