In a medium serving bowl, combine the prepared purple and green cabbage, carrots and parsley. Set aside.
Measure out your seeds into a small skillet. Toast over medium heat, stirring frequently, until the seeds are fragrant and the pepitas are starting to make little popping noises. Pour the toasted seeds into the serving bowl and toss to combine.
Drizzle Lemon Dressing over the slaw and toss until all of the ingredients are lightly coated in dressing. Taste and add an additional tablespoon of lemon juice if the slaw needs a little more zip.