Pint-sized powerhouse Ariana Grande gave her lead singles "Baby I" and "The Way" the acoustic treatment for the staff of Modern Media Luxury alongside Justin Bieber's guitarist Dan Kanter. The intimate performance follows her recent joining of the Biebs' "Believe" tour. The 20-year-old songbird will also be kicking off her own month-long gig dubbed "The Listening Sessions" in Silver Springs, MD August 13. Pre-order her debut Yours Truly, dropping September 3, on iTunes here. Watch the Nickelodeon starlet flaunt her pipes above.