The singer, 20, flaunted her toned tummy in an embellished crop top, which she teamed with some super tight black trousers and boots.
Considering that the temperatures were soaring across the UK on Saturday (19 July), we're very impressed that Cher's smoky eye make up was looking so immaculate!
As the former X Factor contestant took to the stage for her gig, she belted out a few of her favourite tunes.
And it wasn't long before she stepped things up a gear, dancing around and swishing her hair like a pro.
Cher, who married her hairstylist Craig Monk last November, now lives in Los Angeles. She's currently back in the UK to promote her new single Sirens.
And she couldn't wait for her gig at the prestigious nightclub, telling her Twitter followers: "UK! Can't wait to perform at G-A-Y tonight!!! Last chance to preorder Sirens before it's released #GladToBeBackUK."
Cher's also been promoting her new album Sorry I'm Late, which is out on 28 July.
Recently she admitted that she struggled with self-confidence issues during her time on The X Factor in 2010, saying: "Everyone was saying 'you should wear this', and it was confusing.
"I'm much more comfortable and confident with my look and style now."
Well, you certainly nailed it on Saturday night, Cher!
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