01 - Line a baking sheet with parchment paper or a silicone mat to prevent sticking.
02 - Melt the semisweet chocolate in a heatproof bowl over a pan of simmering water, stirring until smooth. Alternatively, microwave in 30-second bursts, stirring after each interval. Stir in ½ tsp peppermint extract.
03 - Pour the melted semisweet chocolate onto the prepared baking sheet and spread into an even rectangle approximately 9x12 inches.
04 - Using the same melting method, melt the white chocolate until smooth. Stir in the remaining ½ tsp peppermint extract.
05 - Drop spoonfuls of the melted white chocolate over the semisweet chocolate base. Use a skewer or knife to gently swirl the two chocolates together, creating a marbled pattern.
06 - Immediately sprinkle the green M&Ms or mint candies, green sprinkles, and mini chocolate chips evenly across the surface while the chocolate is still melted.
07 - Gently press the toppings into the chocolate with your fingertips to ensure they adhere properly.
08 - Refrigerate the bark for at least 30 minutes until the chocolate is completely set and firm to the touch.
09 - Break or cut the bark into irregular pieces and serve immediately, or store in an airtight container.