Put the chocolate chips in a double boiler or in a medium microwave-safe bowl and microwave until completely melted and smooth, stirring as needed. Pour the chocolate onto the prepared baking sheet and use a small off-set spatula to smooth the chocolate into an even 1/4-inch-thick layer. Scatter the popcorn all over the melted chocolate, slightly turning some pieces so they are partially covered in chocolate. Scatter the candy pieces all over the chocolate, slightly pressing to adhere.
Transfer the baking sheet to the fridge and let sit for until completely hardened, 35 to 40 minutes. Remove from the fridge and break into individual size pieces. Store bark in an airtight container in a cool place for up to 1 week.