Line a square baking pan with parchment paper. Set aside.
In a double broiler or microwave, melt the white chocolate until completely smooth, stirring as necessary.
Pour the melted chocolate into the prepared pan. Use a spatula to smooth the melted chocolate out into a single layer. Sprinkle the assorted candy, sprinkles, and roughly chopped Oreos onto the chocolate. Chill in the refrigerator for at least 30 minutes, or until chocolate appears to have set. Remove and cut into pieces.
Notes
I typically melt the chocolate in the microwave in 30 second intervals, stopping to stir between each interval.
I recommend serving the chocolate bark immediately if possible. Otherwise, store in an airtight container at room temperature.