Line a large baking sheet with parchment paper or a silicone baking mat. Set aside.

Melt the white chocolate and pink candy melts together. Use a double boiler or microwave. If using microwave, stir the chocolate every 20 seconds to help avoid seizing. Set aside.

Melt the semi-sweet chocolate. Pour onto prepared baking sheet and spread out into a large rectangle. Drizzle the white chocolate mixture on top. Use a toothpick or knife to swirl the layers together. Decorate the top of the bark with candy hearts and sprinkles.

Allow the chocolate to set uncovered at room temperature or in the refrigerator. (Usually takes about 45 minutes in the refrigerator.) Once hardened, break into pieces as large or as small as you want.

Store bark in an airtight container at room temperature in a cool, dry place for up to 1 week or in the refrigerator for up to 2 weeks.