Rihanna celebrates in Buckhead

We're told she and a group of about 16 arrived at the upscale steak/sushi house and enjoyed a feast of  filet with whipped potatoes and caramelized onions, with chopped jalapenos on the side. Ri-Ri paired the meal with Caymus cabernet sauvignon.

A member of the dining party was celebrating a birthday and of course Rihanna joined in a festive performance of "Happy Birthday" for her friend.

The Prime staff was charmed by the gracious entertainer, who planted a peck on her waiter's cheek as they were leaving.