Line a large baking sheet with parchment paper or wax paper.

Place the crispy rice cereal in a small resealable plastic bag. Squeeze out the air, seal it tightly, and crush the cereal into small pieces using a rolling pin or meat mallet.

In a large microwave-safe bowl, combine the dark chocolate chunks with one tablespoon of heavy cream. Microwave at 50% power for around 2 minutes, stirring every 20 to 30 seconds until the chocolate is fully melted and smooth. Keep an eye on the chocolate, as microwave times may vary.

Once melted, spread the dark chocolate evenly across the prepared sheet using an offset spatula or a silicone spatula. Gently fold the crushed cereal into the melted chocolate mixture.

In a separate small microwave-safe bowl, melt the white chocolate with the remaining tablespoon of heavy cream. Microwave on 50% power for approximately 1 minute, stirring every 20 to 30 seconds until completely melted. Transfer the melted white chocolate into a piping bag with the tip cut off.

Pipe thin spirals of white chocolate over the dark chocolate layer, leaving some space between each swirl. To create spider web designs, drag a toothpick outward from the center of each spiral.

Scatter the Halloween candy, sprinkles, and candy corn across the surface, pressing them lightly into the chocolate.

Let the bark cool at room temperature for about an hour. Afterward, transfer it to the refrigerator for 15 to 30 minutes to fully set. For quicker results, place it directly into the refrigerator for 30 to 60 minutes.

Once firm, break the bark into smaller pieces and enjoy. Store the bark in the refrigerator for up to one week.