01 - Combine sifted powdered sugar, softened butter, peppermint extract, heavy cream, and a pinch of salt in a mixing bowl. Beat on medium speed or stir vigorously until a smooth, pliable dough develops. If dough appears overly sticky, incrementally incorporate additional powdered sugar for a workable consistency.
02 - Scoop dough by 2-teaspoon portions and roll into balls. Flatten each into a disc approximately 1/4 inch thick. Arrange discs on a parchment-lined baking sheet, ensuring separation.
03 - Transfer baking sheet to freezer and chill peppermint discs for 20 to 30 minutes, until firm to the touch.
04 - Place chopped dark chocolate and coconut oil (if using) in a heatproof bowl set over a pot of gently simmering water. Stir continuously until chocolate is fully melted and smooth.
05 - Using a fork, dip each chilled peppermint disc into melted chocolate, allowing excess to drip off before placing back onto parchment-lined sheet.
06 - Refrigerate coated patties for 15 minutes or until chocolate is fully set.