01 - Line a rimmed baking sheet with parchment paper, ensuring it lies flat across the surface.
02 - Place the white chocolate in a heatproof bowl set over a saucepan of gently simmering water, stirring continuously until completely smooth. Alternatively, microwave in 30-second intervals, stirring between each burst, until fully melted and glossy.
03 - Pour the melted white chocolate onto the prepared baking sheet and spread into an even rectangle approximately ¼ inch thick using an offset spatula.
04 - Melt the semi-sweet or milk chocolate using the same double boiler or microwave method. Drizzle it over the white chocolate layer in thin, irregular lines. Drag a toothpick or wooden skewer through both chocolates in fluid motions to create a marbled pattern.
05 - While the chocolate is still wet, scatter the candy robin eggs, pastel sprinkles, and mini chocolate chips evenly across the surface. Gently press the larger candies into the chocolate so they adhere firmly once set.
06 - Let the bark rest at room temperature for 30 to 40 minutes until fully hardened. To accelerate setting, place the tray in the refrigerator for 15 to 20 minutes until completely firm to the touch.
07 - Once fully set, use your hands to break the bark into generous, irregular pieces. Arrange on a platter or store immediately.