Melt chocolate chips and shortening together in a microwave-safe dish, stirring every 30 seconds until smooth.
Prepare a baking sheet with wax paper.
Dip marshmallows one by one into chocolate, covering one half of marshmallow. Carefully shake off excess chocolate.
Holding marshmallow over bowl of peppermint, sprinkle crushed candy onto the chocolate until evenly covered. Stray peppermint pieces will fall back into the bowl below.
Lay marshmallows on one side on wax paper until set. Repeat with remaining marshmallows.
Store in airtight containers, tins, or bags.