Line a baking sheet with parchment paper or wax paper.

Melt at least 1 cup of candy melts in a microwave-safe bowl for 30 seconds. Stop and stir well. Continue to melt in 20-second bursts of heat in the microwave until smooth.

Dip Oreo cookies one at a time in the melted candy melts. Lift the Oreos using a fork or chocolate dipping tool and tap against the sides of the bowl to shake off excess chocolate, then transfer to the prepared baking sheet.

Decorate with Halloween sprinkles, candy eyes, or candy corn before the melted candy melts have a chance to set up.

Allow the covered Oreos to set at room temperature or speed up the process by transferring them to the fridge to harden.