Line a baking sheet with parchment paper or foil and set it aside. This step is important because it prevents the chocolate from sticking and makes removing the bark much easier once it’s set.
Place the white chocolate melting wafers in a microwave-safe bowl and melt according to package instructions. Stir frequently to ensure the chocolate stays smooth and doesn’t overheat.
In a separate bowl, melt the chocolate wafers the same way. Keeping the chocolates separate helps maintain clean swirls and better flavor balance.
Dip the bottom of each Oreo Thin into the melted white chocolate and place it chocolate-side down on the prepared baking sheet. Arrange them close together so they form a solid base.
Pour the remaining white chocolate over the Oreos, spreading it gently to fill gaps and cover the cookies evenly. This layer acts as the foundation of the bark.
Spoon the melted dark chocolate over the white chocolate layer. Use a spatula or knife to gently swirl the two chocolates together for a marbled look.
While the chocolate is still soft, sprinkle the peppermint bits evenly over the top. Press them gently so they stick once the chocolate hardens.
Let the bark sit at room temperature or in the refrigerator until completely firm. Once set, lift it out and cut it into pieces using a sharp knife.