Pentatonix reunited with the one and only Kelly Clarkson [1] for their holiday special on Monday night, and it was nothing short of amazing. During Pentatonix: A Not So Silent Night on NBC, the a capella group and The Voice [2] coach gave a beautiful rendition of "My Grown Up Christmas List." While we never tire of PTX's Christmas covers [3], Clarkson's voice really knocks this performance out of the park. It's pretty much impossible not to get chills [4] over that insane high note at the end. Seriously, we need these two to do duets together more often. Get ready to be blown away!