FIRST LOOK! Katharine McPhee Serves Up a Smile in Broadway's 'Waitress'

Katharine McPhee getting ready to step into the lead role of pregnant pie-maker Jenna Hunterson in the hit Broadway musical Waitress — and PEOPLE’s got the first look at her in beautiful bright blue costume!

The Scorpion actress and American Idol alum, 33, will make her Broadway debut this spring for a limited run at the Brooks Atkinson Theatre beginning April 10.

It’ll be a full-circle moment for McPhee, who had previously starred in NBC’s short-lived and cult-hit TV series SMASH, about the making of a Broadway musical. And it’s a debut that McPhee has patiently anticipated making over the years.

“I’ve waited a long time to do Broadway mostly because I wanted it to be a show that I connected to,” McPhee tells PEOPLE. “I felt Waitress was just that: really well-suited for me.”

It helped that McPhee was a fan of Sara Bareilles, who composed the score to the musical.

“Being a fan of Sara for all of these years, I always hoped she’d write a musical,” McPhee says. “And now to be starring in her show that she wrote music and lyrics to is a total dream.”

For more about Katharine McPhee, pick up this week’s issue of PEOPLE — on newsstands Friday

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.

Based on the Adrienne Shelly’s 2007 movie of the same name, the musical tells the story of a waitress named Jenna in a small town who enters a pie contest in hopes of using the prize money to escape her unhappy marriage.

The role of Jenna was made famous by Keri Russell on the big screen and Tony winner Jessie Mueller, who originated the role on Broadway. Actress Betsy Wolfe has also played the part, as had Bareilles herself twice — first in her Broadway acting debut last March and then again back in January.

She’s currently playing the role now, too and will hand in her apron on March 11.

“I’m passing a pie to @katharinemcphee!” Bareilles, 38, tweeted on Valentine’s Day. “So excited for her to start her shift at the diner as Jenna on April 10. #waitressmusical”

RELATED VIDEO: Here’s How to Make the ‘Devil’s Food Chocolate Oasis Pie’ From the Broadway Musical Waitress

Meanwhile, McPhee released her fifth studio album, I Fall in Love Too Easily, last November.

She appears to be falling in love outside of the album with music producer David Foster, 68, with whom she has been seen smooching.

Dating rumors have followed the pair for months, but McPhee — who has been friends with Foster and first met him on the set of Idol when she was a contestant in 2006 — recently told PEOPLE that she had “zero desire” to address them.

“I think it’s so amusing that people are amused by my love life,” she said. “Here’s how I look at it: I’m not doing anything wrong, so whether people think it’s true or false… there’s nothing bad happening in my life, so people can just say whatever they want.”

Tickets to Waitress can be purchased here.