Sara Bareilles on making her Broadway dreams come true: My life is so different because of 'Waitress' The pop singer-turned-Broadway composer now stars in the Tony-nominated show.

 -- Singer-songwriter Sara Bareilles is known for her hit singles like “Brave” and “Love Song,” but the multi-Grammy nominee said seeing her name in shining Broadway lights is a dream come true.

“The first time I saw the marquee, I completely lost my mind. I was just about beside myself,” Bareilles told ABC News “Nightline.” “I mean to be as cheesy as I can be like a childhood fantasy coming true in a way I would never have imagined. So I'm just I'm really, really so happy.”

Bareilles wrote the music for and now stars as the lead actress in the Broadway musical, “Waitress,” but she laughed off any notion of calling herself a “Broadway star.”

“I’m just a shmoobee [sic] from the sticks,” she said. “I have no business carrying myself like some diva.”

In the show, Bareilles plays Jenna, a small-town waitress full of big dreams and in search of a new and better life far from her abusive husband.

She stepped in for Tony winner Jesse Muller for the lead and now does eight performances a week, which she said was “completely, totally intimidating.”

Now Bareilles’ name appears alongside other Broadway giants, such as Glenn Close, who stars in “Sunset Boulevard,” and “Hello, Dolly!” star Bette Midler. During her first week as lead actress, the show brought in over $1 million in ticket sales -- a record for the Brooks Atkinson Theatre where the show is performed.

“I don't want to fake anybody out and make them think I'm a great actress,” Bareilles said. “What I want to do is come and do my best work and work really hard at being great at honoring the craft. I'm not trying to, like, bamboozle anybody. I want to do good work in the world.”

“Waitress” marks Bareilles’ second role in what has become a passion project for her. She first left the world of pop music to join the “Waitress” production staff as lead composer.

“I was getting fatigued of the cyclical nature of being a pop artist where you write a record, record a record, go on tour, promote, come home, do it all again,” Bareilles said. “So I just was ready to work on something different.”

For three-and-a-half years, Bareilles worked tirelessly to bring the show to life -- one song at a time.

“I rewrote the opening number 40 times,” she said. “I wanted to absolutely tear my hair out and throw people across the room. It was so frustrating. But you know all of that again that pressure cooker is I think actually kind of an exciting place to be.”

Other musicians, including Cyndi Lauper and Carol King, have brought their music to the Broadway stage. But Bareilles joins the ranks of Sting and Green Day’s Billie Joe Armstrong to be both the composer of and the actor in her own Broadway show.

Bareilles’ songs for “Waitress” recently landed her a Tony nomination for best original score. The show currently has four nominations total, and winners will be announced in June.

In addition to her Grammy nods and successful Broadway show, Bareilles also penned a best-selling book called, “Sounds Like Me: My Life (So Far) in Song.”

Her fans adore her music because she’s not afraid to get personal. She said her hit single “Brave” is “a love letter” to one of her best friends who “was struggling with coming out as an adult.”

“I just wanted to say to them, like, ‘It’s OK to be yourself, there’s love waiting for you,’” Bareilles said.

The Broadway show is based on the 2007 film, “Waitress,” starring Keri Russell. The indie film was written and directed by Adrienne Shelly, who was killed in 2006 before the movie was released.

“It felt like this beautiful collaboration with Adrienne Shelly who's no longer with us sadly,” Bareilles said. “But we get to carry on her legacy through the film, and her producer on the film and her family have worked very closely with us and been incredibly supportive.”

Another example of sisterhood behind the “Waitress” project is that it became the first Broadway show with an all-female creative group.

“I love the example that that sets for a young choreographer or a young scriptwriter, a young composer who wants to see more of themselves reflected in the community at large,” Bareilles said.

And another special touch is that the staff makes the theater smell like pie during performances -- with real, fresh-baked pies. Pie consultant Stacy Donnelly is the woman behind all the colorful pies used on stage and the 2,000 pies sold weekly inside the theater.

“We have a little convection oven that's hidden away and about 40 minutes before the doors open and we start baking a fresh apple pie every day,” said Donnelly.

As to whether she would write another Broadway show, Bareilles said she would love to “revisit the composer hat” for a future project.

“My life is so different because of ‘Waitress,’” she said. “The people that I'm close to, the things I do professionally, my colleagues, my best friend and my boyfriend, like all of these things have come to me because of the show. And it's really beautiful.”