Fresh from winning the live final last weekend (Saturday 13 December), Ben performed at the famous venue exactly a week later - and got more than he bargained for!
After his set was met with thunderous applause from his fans, playful event owner Jeremy Joseph presented Ben with a celebratory present.
Former van driver Ben, 29, was handed a yummy-looking cake honouring his bid for the Christmas number one.
But, when Ben later sat down by the edge of the stage to continue his set, naughty Jeremy crept up behind him to squidge some of the cake into Ben's handsome face!
A surprised Ben showed his sense of humour when he laughed off the joke, and then began to throw cake back at Jeremy and at the audience...
We wish we'd been there!
Ben obviously enjoyed the unusual gig, tweeting afterwards: "Thank you @ JeremyJoseph .. That was fun!"
Croydon singer Ben is hoping his single 'Something I Need' will top the charts.
Her performed his debut single live during the Text Santa appeal show on Friday night (19 December).
Have you bought Ben Haenow's single? Tell us in the comment box below and you could win £50!
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