Nikka Graff Lanzarone and Mo Brady's Broadway podcast celebrated its first anniversary in June.
Broadway @ The Art House will welcome the crooner back later this summer.
The musical will be seen as part of the annual BBC Proms.
Additional performers for the benefit concert have been announced.
The off-Broadway satirical send-up has announced plans to close next month.
The Tony-nominated Broadway star has booked a gig with her theatrical indie-pop girl group.
Composer Scott Alan will accompany the "Unique" star.
Adam Jacobs, Tony winner James Monroe Iglehart, and more will be on hand to greet fans and autograph albums.
The group will celebrate with a launch event at INC Lounge.