In a medium heatproof bowl, microwave chips and oil in 20-second increments, stirring between each, until melted and smooth, about 1 minute total. Add cake mix and stir to combine.
On a baking sheet, toss popcorn and butter. Drizzle with chip mixture and sprinkles and toss again to combine. Top with more sprinkles, if desired.
Refrigerate until set, 20 to 25 minutes.
