Sara Bareilles on Breaking Into Broadway and Why She Sang 'The Little Mermaid' at 'Waitress'

A veteran singer-songwriter who has been touring the world for more than 10 years, Sara Bareilles has witnessed plenty of onstage mishaps and behind-the-scene emergencies. But with her first musical, Waitress in previews on Broadway, the Grammy nominee has been introduced to an entirely new kind of disaster, and, on March 30 she encountered what she called the “most unexpected thing to happen yet.”

At a preview performance of the musical adaptation of Adrienne Shelly’s 2007 film of the same name, a series of technical malfunctions took place, one after another, until the show had to be brought to a halt. Bareilles, who was sitting in the audience, immediately climbed onstage and began to entertain the crowd, performing a song that had been cut from the musical as well as “Part of Your World” from Disney’s The Little Mermaid.

“For some reason there were gremlins in the building that night,” Bareilles told PEOPLE, adding that it was the first time anything had malfunctioned behind the scenes. “Me being a total ham, I said, ‘I’ll sing for the audience.'”

“It’s a slightly cheap trick on my part – if something goes wrong in a show of mine, I have found that singing The Little Mermaid is a go-to to get everybody onboard and keep them entertained. You hope that the technical difficulties are resolved by the time you’re done. It’s not the first time I’ve done it but I think that was my favorite time I’ve done it.”

Waitress marks Bareilles’ first foray onto Broadway, but she is no stranger to musical theater, having performed as a child with her sisters as well as her local community. But before Tony-winning director Diane Paulus invited Bareilles to join the project, composing for the stage had not occurred to her.

Four years into the project, she said the breadth of work still surprises her as well as the new challenges it presents – for example, writing a song about taking a pregnancy test (“There’s not a time in my pop career I can think of where I could try to work in lyrics about peeing on a stick”) – or composing just the right opening number – “I’ve been told these horror stories from Broadway, that traditional pickup is finding the right opening number. I have rewritten that song – we probably have 10-15 versions of that song in our shared creative dropbox.”

With Waitress opening April 24, Bareilles joins the ranks of many pop singer-songwriters who have recently composed for Broadway.

Duncan Sheik

After becoming a household name with his 1996 hit “Barely Breathing,” Sheik’s compositions first appeared on Broadway in 2006 with Spring Awakening, which set controversial German play to rock songs such as “The Bitch of Living” and “Totally F ed.” The show went on to win eight Tonys, including best musical and best original score. Angst and anger seem to be Sheik’s penchant for musicals; his latest work, American Psycho, an adaptation of Bret Easton Ellis’ book about a successful Manhattan businessman who also happens to be a serial killer, opens on Broadway April 21.

Cyndi Lauper

Lauper’s resume was already packed – singer, songwriter, actress and activist – when she made her Broadway composing debut with 2013’s Kinky Boots, a stage adaptation of the 2005 film of the same name. Based on a true story, Kinky Boots tells the story of Charlie, the struggling owner of a shoe factory, who collaborates with Lola, a drag queen who inspires Charlie to manufacture custom footwear for Lola and her friends. The musical snagged the 2013 Tony Award for best musical, and Lauper won best original score – the first woman who had not worked with a man to do so.

Sheryl Crow

All she wants to do is have some fun! And she is, serving up the musical adaption of the cult favorite film Diner. Crow, who has been composing for more than 20 years and earned 32 Grammy nominations – and won nine – was ready to try something new when the film’s writer and director, Barry Levinson, asked her to compose the score. Diner has been dished up in Washington, D.C. and Delaware, and fans are hopeful it will be served on Broadway soon.

Sting

The prolific Grammy winner had been suffering from writer’s block until he began composing the autobiographical musical The Last Ship, which chronicles the struggles of a shipbuilding industry and a young man who returns to the hometown he abandoned to hopefully win the heart of the girl he had left behind.

Crediting the musical with motivating him to write again, Sting also joined the Broadway cast and received Tony Award nominations for best score and best orchestrations.