The `Country Strong` actress has showcased her vocal talents at a number of high-profile events this year but she still gets scared when she performs, and `Glee` star Matthew Morrison says she was equally terrified when they recorded a track for his self-titled debut album together.
He said: "She was nervous. She`s such a good singer and she gets nervous to sing, which is funny because she sang at everything this year - the Grammys the Oscars - and she was such a nervous wreck every time she had to go out there, but she was amazing every single time.
"She didn`t really know the song; obviously she knew `Somewhere Over the Rainbow,` but she didn`t know that version so I taught it to her in the studio and she picked it up really fast because she`s got a great ear."
As well as collaborating with Gwyneth, Matthew`s album also features a duet with Sir Elton John and the actor was terrified of asking the musical legend to work with him - and incredibly surprised when he said yes straight away.
He recalled to AOL: "That one was tricky because I don`t really know him that well; I didn`t back then. I went to his Oscar party and then he invited me to this White Tie and Tiara Ball in London that he has every year, and then I found out he was a `Glee` fan.
"My hands were sweating and I walked up to him and was like, `Hey, Elton how`s it going?` He`s a lovely guy, and I said, `I`m doing this album and I would really like to sing with you on it if you would do that for me,- and he was like `yeah, absolutely!` I was like, -"Oh, man that was just so easy.`
"It was one of those things where, three days after we recorded it, it finally sunk in and I was like, `Oh my God, I just did a duet with Elton John.` It was very surreal."