Entertainment Theater Order Up! Sara Bareilles Rehearses for Her Broadway Acting Debut in 'Waitress' — See the Pics! PEOPLE's got the first look at Sara Bareilles in rehearsal for her upcoming Broadway acting debut in Waitress By Dave Quinn Dave Quinn Dave Quinn is a Senior Editor for PEOPLE. He has been working at the brand since 2016, and is the author of the No. 1 New York Times best-selling book, Not All Diamonds and Rosé: The Inside Story of the Real Housewives from the People Who Lived It. People Editorial Guidelines Published on March 21, 2017 01:37PM EDT Photo: Joan Marcus Sara Bareilles will make her Broadway acting debut next week — joining the cast of Waitress, the hit 2016 musical whose score she composed — and PEOPLE has the exclusive first look at the 37-year-old singer in rehearsal. The “Brave” songstress will step into the lead role of pregnant pie-maker Jenna Hunterson for a limited 10-week run at the Brooks Atkinson Theatre. The role was made famous by Keri Russell in Adrienne Shelly’s 2007 movie of the same name, about a waitress in a small town who enters a pie contest in hopes of using the prize money to escape her unhappy marriage. In the photos, Bareilles can be seen cozying up to costar Chris Diamantopoulos—who also joins the cast on March 31. He takes the role of Dr. Pomatter, Jenna’s OB/GYN (and love interest). Joan Marcus Joan Marcus “Sugar, Butter, Broadway,” Bareilles wrote on Instagram in February, announcing her full-circle role in the show. “It is with unabashed delight that I announce that my childhood dream is coming true and I’m gonna be on Broadway!!!! I am joining the cast of WAITRESS!!” Alongside the excited message, Bareilles posted a throwback photo of herself side-by-side with a picture in costume for the musical. RELATED VIDEO: How Does the Broadway Musical Waitress Make Their Theaters Smell Like Pie!? Her note continued, “In a few short weeks I will be stepping into the role of Jenna Hunterson, and I’m just beside myself! This show, the people who made it, and these characters have become more precious to me than I could ever say. It will be an incredible privilege to join the cast onstage and tell this beautiful story.” After revealing her start date, the singer joked, “Panic attacks available now.” Bareilles’ run in Waitress is currently scheduled through June 11. Tony winner Jessie Mueller, who originated the role on Broadway, will play her final performance on March 26. FROM COINAGE: 9 Healthy Kitchen Staples That Cost Less Than $1 Per Serving Waitress is the first Broadway musical ever to boast an all-female creative team. In addition to Bareilles’ music and lyrics, the show features a book by Jessie Nelson, choreography by Lorin Latarro, and direction from Tony Award winner Diane Paulus. A popular ticket, producers announced in January that the show had recouped its $12 million investment. Bareilles’ last album of original material was 2013’s The Blessed Unrest, which was nominated for an album of the year Grammy. She also released a cover album of Waitress tunes in 2015 — including the ballad “She Used to Be Mine,” which was tapped as the compilation’s lead single. Tickets to Waitress can be purchased here.