Remy Gonzalez

Dressed in his yellow jail uniform -- "Cake Boss" co-star Remy Gonzalez strolled into a NJ courtroom this morning ... where the man accused of sexually assaulting a minor learned that he will face a grand jury. As we first reported, Gonzalez -- who is married to "Cake Boss" Buddy Valastro's sister…

TMZ has learned one of the stars of "Cake Boss" has been arrested for sexually assaulting a minor. According to law enforcement sources Remy Gonzalez is currently being held in Morris County Jail in New Jersey ... he's been there since August 18 when cops arrested him. Officials tell us Gonzalez…