Remove stems from apples. Insert a dowel into each apple at the stem end.
In a microwave-safe bowl, combine candy melts and oil; melt according to package directions. Dip apples in candy until evenly coated, making sure some green peeks out. Allow excess candy to drip back into bowl. Sprinkle chopped pistachios around top of each candycoated apple.
Place apples on a parchment-paper-lined baking sheet to dry.