01 - Line a 9x13 inch baking sheet with parchment paper and set aside.
02 - Melt the dark chocolate in a heatproof bowl over a pot of simmering water, stirring frequently until smooth and glossy.
03 - Stir the peppermint extract into the melted dark chocolate until fully incorporated.
04 - Pour the dark chocolate mixture onto the prepared baking sheet and spread evenly to about 1/4 inch thickness.
05 - Melt the white chocolate using the same method, taking care not to overheat or scorch.
06 - Drop spoonfuls of white chocolate randomly over the dark base, then drag a skewer or toothpick through both chocolates to create a marbled pattern.
07 - Sprinkle crushed peppermint candies evenly across the surface while chocolate is still melted.
08 - Refrigerate for 45 minutes until completely firm and set throughout.
09 - Break the bark into irregular pieces and store in an airtight container at cool room temperature or refrigerated.