American Idol Katharine McPhee to star in Broadway's 'Waitress' beginning April 10 02/16/2018 Katharine McPhee has been tapped to play the role of Jenna in the Broadway musical Waitress. Read More RELATED NEWS Katharine McPhee leaves David Foster tour after "horrible" family tragedy'American Idol' alum Kellie Pickler's husband Kyle Jacobs dead from apparent suicideKatharine McPhee gives birth to first child with David Foster TAGS: American Idol Katharine McPhee Sara Bareilles Jessie Mueller Adrienne Shelly Scorpion Waitress