She belted out her latest new single 'Run' off latest album 'Big Fat Lie' and even showed Cheryl how to sing live too. Cheryl was previously dumped from the now axed X Factor USA just so that Nicole could replace her on the panel.
Their differences further escalated when Cheryl shaded Nicole in her autobiography. But the best revenge? Singing your ass off in front of the very rival who is widely known for having vocals thinner than tracing paper. Nicole revealed that her performance - which was labelled 'boring' by several viewers on Twitter - was affected by a power failure, meaning laser lighting could not be added to her set.
She later told presenter Sarah on ITV2 spin-off show the Xtra Factor: "It doesn't even matter if you had lasers or whatever, as long as you sing your heart out". And that she certainly did! Check out her heartfelt performance below!