Mix your kale, cabbage, and carrots with orange juice, salt, and pepper. You'll want to massage the kale a bit to soften its leaves and reduce its bitterness.
Add the red onions, mayo, oil, and honey, and toss to combine.
Mix in the pepitas, or use them as a topping (so they stay crunchy, I recommend using them as a topping if you're not eating it right away), and enjoy!