Here’s a good reason to tune into tonight’s ninth season finale of American Idol: The original Idol powerhouse Kelly Clarkson and Season 3 champ Fantasia will perform a duet, “Together We Are One,” as a final send-off to departing Idol judge Simon Cowell!

The American Idol finale — featuring finalists Crystal Bowersox and Lee DeWyze –kicks off tonight @ 8PM on Fox.