01 - Line a 9x13-inch baking sheet with parchment paper, ensuring complete coverage to prevent sticking.
02 - Place chopped dark chocolate in a heatproof bowl over a pot of gently simmering water, stirring frequently until completely smooth and glossy. Alternatively, microwave in 20-second intervals, stirring between each burst.
03 - Remove the melted dark chocolate from heat source and thoroughly incorporate the peppermint extract, ensuring even distribution.
04 - Pour the mint-infused dark chocolate onto the prepared baking sheet. Use an offset spatula to spread into a uniform rectangle approximately 1/4 inch thick.
05 - Melt the chopped white chocolate using the same double boiler method, stirring until completely smooth and free of lumps.
06 - Drop spoonfuls of melted white chocolate across the dark chocolate surface. Use a skewer or toothpick to gently swirl through both chocolates, creating a marbled pattern without overmixing.
07 - Immediately sprinkle crushed peppermint candies and mini chocolate chips over the surface while chocolate remains warm. Press lightly with fingertips to ensure adhesion.
08 - Transfer the baking sheet to the refrigerator and chill for at least 1 hour, or until the bark is completely firm and breaks cleanly when tested.
09 - Remove the chilled bark from the refrigerator. Break into irregular pieces by hand or use a sharp knife. Store in an airtight container at cool room temperature for up to 2 weeks.