KING OF QUEENS” star KEVIN JAMES can’t keep the pounds off – be­cause he’s hiding a secret stash of chocolate treats behind the healthy food in his fridge!

Last summer, while the 47-year-old actor was in Massachusetts filming “Grown Ups 2,” he was under the care of a personal chef who put him on a strict organic diet to help him lose weight for his role in the upcoming movie “Valet Guys.”

“When he wasn’t working on the set, Kevin would exercise downstairs with his trainer in the house he was leasing,” said a source. “They also had a punching bag outside, and he would work out on it with this guy for an hour. Meanwhile, his chef, Nicole, would make mostly fish with veggies or salads and keep them ready for when Kevin was set to eat.”

But unbeknownst to Kevin’s chef, his trainer AND his devoted wife, Steffiana, the actor was dipping into a king-size bag of Reese’s Peanut Butter Cups he’d stashed in his fridge!

“It was his little secret,” the source added. “And he’d hide everything behind the low-calorie food!”

Kevin’s weight issues are nothing new. After shooting up to over 300 pounds, he went through an extreme routine in 2010 and lost 67 pounds for his role as a teacher-turned-mixed martial arts fighter in “Here Comes the Boom.”

But after filming ended, he says he allowed himself to have a “little fun” – and put all the weight back on.

Kevin may need a miracle if he wants to get his bad eating habits under control – and insiders wouldn’t be surprised if he gets one!

While on the set of “Grown Ups 2,” the devout Catholic had priests flown in from L.A. every weekend to say Mass for his family and pray with them. He also kept a set of rosary beads on each post of his bed in the leased house and regularly attended the local church.

“Kevin is super Catholic,” noted a source.