The 19-year-old pop star has created a range of clothes for Lipsy and if she could dress any celebrity she would love to style the 'My Sister's Keeper' star.
She told BANG Showbiz: "I'd feel very lucky if anyone wore any of my designs. But I don't know. If we're talking anyone, someone like Julia Roberts or Cameron Diaz. That'd be so weird and funny. Cameron wearing my dress at The Oscars. That'd be so funny."
The 'Boys and Girls' hitmaker also admits she was "surprised" when she saw a festivalgoer wearing one of her designs, as was the girl when Pixie ran up to her.
She said: "I was at a festival during the summer and I saw someone in my dress and jacket from the festival range and I had to stop her. I rushed over and was like, 'Oh my God, you look amazing!' She was shocked and I was shocked, we were both shocked!"
Just as Pixie is a fan of Cameron Diaz she is also a big fan of high-end fashion, and prefers wearing designer clothes to high street brands.
She said: "I like high-end. It's good to have a mix I think, but if I had to pick I'd say high-end.
"I borrow a lot of stuff from different designers, but I always want to keep them! The trouble is I lose stuff really easily, my mum is always like, 'Do not lose anything!' "