Liam Payne took a cake decorating class.

The One Direction hunk and his girlfriend Sophia Smith paid a visit to Carlo's Bakery in New Jersey on Wednesday (06.08.14) to learn the art of icing some sweet treats after admitting to being a ''huge fan'' of 'Cake Boss', the reality TV show about the bakery.

Carlo's employee Adam told E! News: ''It was totally unknown. He tweeted at Buddy [Valastro, owner], and then he called the bakery [about coming in].

''They were just there to have fun. Totally spur of the moment. They didn't get to meet Buddy, Buddy is overseas, but they met his sisters.''

However, as well as the private decorating class - in which he decorated a blue fondant cake with white icing while Sofia worked on a pink and purple tie dye dessert - Liam shocked customers when he jump behind the counter and served them.

Adam explained: ''He put on a Carlo's Bakery shirt, and he came behind the counter and helped out some customers. He even took photos with fans and signed some autographs.

''We had a lot of fun. The bakery loved having him.''