This was no sweet surprise.

A customer dissatisfied with the amount of icing on his cinnamon roll bashed a Brooklyn food worker in the face with a metal napkin dispenser, cops said Monday.

A 25-year-old Cinnabon employee was berated and attacked around noon Sunday by an unhinged customer with a serious sweet tooth who visited the bakery’s King’s Plaza mall location, cops said.

The unidentified man ordered his afternoon snack and went on his way, only to return to the counter, unsatisfied with the amount of icing on his roll, several minutes later, according to sources.

The man called the employee a b–ch and demanded more icing, which she gave him after he paid an additional fee — but he was still unsatisfied and rudely asked for a new cinnamon roll, sources said.

While the employee made a fresh roll for the man, he continued to gripe and call her a b–ch, at which point she decided to refund the man’s money, and tossed the new cinnamon roll into the garbage, sources said.

While she worked the register, the crazed customer threw a handful of napkins at the employee’s face, then picked up the metal napkin container and bashed her in the head with it, cops and sources said.

The employee refused medical attention at the scene, and the man fled in an unknown direction, cops said.