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You can create even zig-zag lines by moving your arm back and forth in a uniform way across the entire sheet of cake balls. For decorating the cake pops, you can either sprinkle chopped chunks or use a food processor to create finely chopped pieces. You can also use other nuts, like peanuts, as a substitute if walnuts are unavailable. To ensure a hard coating and for any toppings to appear more uniform, place the cake balls in the freezer or refrigerator for about an hour or two.
Drizzle additional melted chocolate on top. Sprinkle the walnuts on top. Chill the cake balls again. Finished.