Nicki Minaj celebrated her 31st birthday yesterday, keeping things relatively low-key with a dinner at the newly-opened Philippe Chow in Beverly Hills. The YMCMB superstar pulled up in her $700k custom Lamborghini Aventador with longtime boyfriend Scaff Beezy by her side, and was joined by a handful of her closest girlfriends. Check out some of the pics from the night in the gallery, including her crazy cake and even crazier birthday gift!