Mariah Carey & Nick Cannon Are Back Together For Dinner ... And The Kids

Mariah Carey and Nick Cannon are official ... so Nick proclaimed Thursday night as he squired her out of a fancy restaurant.

The two dined at Mr Chow in Bev Hills and left together in the same car.

Nick doesn't think they ever really went their separate ways, even though he had a baby with another woman and she was engaged, dumped the guy and then got a new BF.

Fact is ... relationships come and go, but kids are forever, and they have 2.