Robin Thicke returned to his roots for his new album-release party, hosting the bash at Butter, where he celebrated his first album seven years ago. The crooner, who was full of surprises at the soiree, treated stars including Usher, Michelle Trachtenberg and John Legend to a full concert, taking over a stage with a 10-piece band and pulling Leighton Meester from the audience to join him in singing “Somebody To Love” as her beau, Sebastian Stan, cracked up. While Thicke performed, Beyoncé and Jay-Z held court at a table with Andre Balazs, who brought along a blond guest. “Beyoncé was really enjoying the performance. She sang along to Robin’s songs and smiled and clapped as Leighton performed while drinking Svedka martinis,” said a spy. Butter owners Scott Sartiano and Richie Akiva had another reason to celebrate: They’re opening an outpost of the Lafayette Street hot spot next year in Charlotte, NC.