But her first big break came after she auditioned for "American Idol" in 2006. Her strong vocal ability and stage presence made her a favorite to win the singing competition series. Unfortunately, she came in second to Taylor Hicks.
But that didn't stop the now-36-year-old entertainer. McPhee went on to star as one of the leads in the musical drama TV series "Smash" and land the lead in the Broadway show "Waitress."
Check out her other top performances below:
McPhee played Paige Dineen in the CBS drama series from 2014 to 2018. She worked with a team of people with high IQs to help solve the world's most complex problems and stop security threats.
"She's unapologetic. She's had to have more responsibility, and she has a kid, she's a little more grown-up, she's older. So I don't know if it's edgy. It's just more -- not aggressive, but very direct. And I like that, because that's a fun thing to play," McPhee told BuzzFeed about playing Paige in a 2014 interview.
The California native played Karen Cartwright on the NBC musical drama series that aired from 2011 to 2013.
The character was an aspiring theater star competing to land the lead role in an upcoming Broadway musical about Marilyn Monroe, so McPhee was able to combine musical theater, dance, singing and acting into one role.
In a 2012 interview with Reuters, McPhee said, "In this part, I get to live the best of both worlds. I get to play a character who wants to live on stage."
McPhee landed the lead role of Jenna in the Broadway musical with music and lyrics written by Sara Bareilles.
"'Waitress' is a story that’s universally relatable. It’s a journey of someone trying to discover what self-love looks like. It’s an empowering story that everyone struggles with: feeling stuck at a time in their life," she told Broadway Inbound in 2018. "How many of us have something we can't do on our own, or that we’re trapped in a situation? It’s the perfect combination of a universally relatable story and beautiful music."
The wife of composer David Foster became a household name during her time on the singing competition series after auditioning at just 21 years old.
McPhee ultimately placed second but made her mark with stunning performances of "Over the Rainbow" and "I Have Nothing."
"I had very little performance experience so what I learned was that to be a great performer you’ve just got to do it — you’ve got to find spaces to experience and learn and keep trying," she told Reader's Digest about her time on "Idol."
"I also learned that preparation is the most important thing. I pride myself on being as prepared as possible now because that’s what gives you confidence," McPhee added.