01 - Line a baking sheet with parchment paper to prevent sticking.
02 - In a heatproof bowl set over simmering water, melt semi-sweet chocolate, stirring until smooth. Incorporate 1/4 teaspoon peppermint extract.
03 - Spread melted semi-sweet chocolate evenly into an 8x10 inch rectangle on the prepared sheet. Chill in the refrigerator for 10 minutes until nearly set.
04 - Using the double boiler method, melt white chocolate until smooth. Stir in remaining 1/4 teaspoon peppermint extract.
05 - Pour melted white chocolate evenly over the chilled semi-sweet layer and gently spread to cover fully.
06 - Immediately sprinkle crushed peppermint candy canes evenly on top, pressing lightly to adhere.
07 - Refrigerate for at least 30 minutes until the bark is completely firm.
08 - Break or cut the set bark into pieces. Store in an airtight container at room temperature for up to one week.