Sara Bareilles will take on the role she wrote for Broadway when she steps into the shoes of Jenna in "Waitress." The "Brave" singer-songwriter announced via Instagram this morning that she'll take over the character originally played by Jessie Mueller starting March 31. Bareilles, who wrote the songs and lyrics for the show, had a heavy hand in the promotion of the production's music, releasing a radio-ready rendition of the soundtrack as sung by her (with Jason Mraz filling in as Dr. Pomatter) and performing alongside Mueller at the 2016 Tony Awards. 

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Mueller announced she'd be leaving the production in December; her last show will be March 26. The 10-week run (wrapping June 11) will be Bareilles' first on Broadway, but not her first for musical theater — as you may have caught her in the live concert performance of "The Little Mermaid" at the Hollywood Bowl last June. 

"Jessie Mueller has been an absolute dream come true in this role and I'm deeply honored to get to take a turn at embodying our beloved Jenna (and hopefully remember my lines along the way)," the five-time Grammy nominee wrote on Instagram. "My first show is MARCH 31. Panic attacks available now."

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"Waitress" the musical was based on the late Adrienne Shelly's 2007 romcom of the same name, starring Keri Russell and Nathan Fillion in the lead roles. It was nominated for four Tony Awards and one Grammy following its Brooks Atkinson Theatre debut and is set to embark its official U.S. tour come October.