Spread popcorn and pretzels on parchment paper-lined cookie sheet.
In a disposable decorating bag, melt candy in microwave at 50 percent power for one minute; remove bag and knead. Continue melting candy for 30-second intervals at 50 percent power until completely melted. Snip off end of bag and drizzle melted candy over popcorn mixture; immediately add sprinkles. Let stand until candy has hardened, about 20 minutes. Break into pieces to serve.