Roll ⅓ of the dough in between two silicone baking sheets
until ~½" thick. Sprinkle ⅓ of the rainbow confetti onto the partially rolled out dough, then roll again in between two silicone baking sheets, this time until it's ~⅛" thick. Use a 2" circle cookie cutter to punch circles into the dough. Peel away the dough surrounding the circle shapes, putting the dough back into the stand mixer bowl, and transfer the silicone sheet with the circles onto a cookie tray.