Add the dark chocolate chips to a small microwave-safe bowl. Microwave on high for 30 seconds. Stir.
Microwave again for an additional 30 seconds. Stir again. By this point, your chocolate should be smooth and shiny. If there are still large lumps, microwave for an additional 15 seconds and stir again.
Dump the chocolate onto the parchment paper and spread it out until it is ¼” thick. This is easiest to do with an offset spatula.
Add any sprinkles, candy, or decorations while the chocolate is still wet— work quickly as it will start to harden immediately.
Repeat with the remaining two chocolates.
Transfer the chocolate bark to the freezer and allow it to sit for at least 30 minutes.
While the chocolate bark is still frozen, break it into large shreds with your hands (or with a sharp knife).
Store in an airtight container in the refrigerator for up to 2 days.
Notes
To make shapes, transfer ¼ cup of melted white chocolate to a plastic bag. Cut the very corner tip of the bag off and use the chocolate to pipe the ghost or spider web design. If your candy wafers start to separate or clump, add 1 tablespoon of solid vegetable shortening. Microwave for 30 seconds and then whisk it vigorously.