Er, where was our invite guys?
The X Factor judge, who turned 38 yesterday, looked absolutely incredible in a hot pink leather cropped top that drew attention to her wasp waist and she covered up her lengthy legs in a pair of billowing, high-waisted palazzo pants.
The former Pussycat Doll may have been wearing the highest platform heels we've ever seen but she strolled past the paparazzi and up the stairs of swanky Restaurant 34 in Mayfair with ease.
Proving that she wouldn't look out of place on a catwalk, Nicole flipped and swished her seriously stunning tousled tresses (we're loving the copper-toned highlights a la Geordie Shore's Vicky Pattison!) before grabbing the hand of a pal and heading on inside.
Nicole - who judged during series 9 and 10 of the X Factor but is returning this year alongside Sharon Osbourne and Louis Walsh - kicked the fashion rulebook to the kerb and dressed her plump pout in a slick of pillar box red lippie which could have clashed against her spray-on fuchsia number...
...but she totally managed to pull it off.
The star studded bash is said to have continued well into the early hours.
This year, The X Factor is bringing back the intimate room auditions for series 13, which means contestants must impress the judges in a private audition room, before being propelled onto a stage to sing their heart out in front of an audience of thousands.
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