The West Actress will be teaming up with Andrew Lloyd Webber on the series, which will search for a talented singer and performer to star in a special arena tour of musical Jesus Christ Superstar.
Amanda, who almost died when giving birth last month, joked on This Morning about the role: "As I have a West End background, and I nearly met Jesus the other week, I'm the best qualified."
She added: "We haven't signed on the dotted line yet, but I am. I'm not sure if I'm supposed to talk about it!"
Auditions for the show started earlier this year with callbacks taking place last week. The show will air on ITV1 in the summer.
"They've gone all over the country and Andrew said they've even had some girls auditioning to play Jesus as well," Amanda continued. "I'm not sure they've sorted out the judging panel yet but it's going to be a huge arena tour and it'll go worldwide."