And no...we're not talking about her boyfriend Russell Brand.

Katy Perry's secret weapon to warming up her voice?

Greasy potato chips.

Singer Nathaniel Motte collaborated with Perry and said:

"The only thing that Katy asked for in return for featuring on our single was a massive portion of greasy chips.  Apparently the grease is her secret trick for opening up the airwaves and making her voice sound great."

Hmmm....go, figure!