The X Factor winner made a special appearance at G-A-Y in central London, where was surprised onstage by Naomi Campbell, said to be a big fan of the singer.
CLICK ON PHOTOS FOR GALLERY
Sam was presented with a large teddy bear and a huge cake by nightclub owner Jeremy Joseph before performing her single, From This Moment On. But the evening quickly descended into chaos as Sam and Jeremy got into a cake fight.
The pair were seen completely covered in sponge and icing after throwing cake at each other in her dressing room.
Food fight! Sam and nightclub owner Jeremy ended the evening covered in cake
Jeremy later tweeted, "Can't wait until we get to see the backstage photos of G-A-Y tonight, let's just say @SamBaileyREAL wears cake so well xx."
On Sunday morning, he tweeted the 36-year-old writing, "@SamBaileyREAL I still stink of cake, I'm sending my mate Mr Kipling to Leicester to find you for round 2 xxxx."
Pregnant Sam appeared at the London hotspot on Saturday night to celebrate the launch of her album – and the following day it was confirmed that she had taken the top spot in the charts.
But the down-to-earth star wasn't going to spend the day waiting by the phone. Instead she spent Mother's Day focused on her two children, Brooke, eight, and Tommy, four.
The singer at home with husband Craig and their children, Brooke and Tommy
"It isn't about me sitting in bed and being spoilt rotten," she told the Sunday People. "I just want to be with my kids doing what they want to do.
"It's amazing to be touring the country performing and having all this success, but the sacrifice I have to make is not seeing my kids every day, which can be heart-breaking. The day is all about spending every minute with them."
Revealing her plans for the day, she added, "It will be amazing to be number one, and if I hear my mobile go off I'll answer it, but if I'm taking my bowling turn or buying drinks for the kids I'll probably miss the call.
"And to be honest, I think the kids would be more excited about getting a perfect strike."