Candide at Carnegie Hall, 2006

I was searching online for videos of Barbara Cook singing "Glitter and Be Gay" and I stumbled across a video that is described as "Candide at Carnegie Hall, 2006". This particular clip shows Cook singing the beginning of "Make Our Garden Grow" and she is joined by Kelli O'Hara and Sebastian Arcelus later in the piece. I searched for information about this particular concert but could not find anything. Does anybody know the details about this concert? Did Kelli and Sebastian actually play roles in the concert or did they just sing during the finale?

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