Heat the oven to 400ºF.
In a small bowl, whisk together the honey and Dijon mustard.
Add the chicken, potatoes, and parsnips to a large mixing bowl. Pour in half the honey mustard and mix until everything is coated. Pour everything onto a sheet pan. Spread into a single layer, flipping the potatoes over so the cut side is down. Season with salt and pepper.
Transfer the pan to the oven and bake for 30 minutes.
Coat the kale with the olive oil. Season with salt and pepper. Add the the baking pan; cook for an additional 10-15 minutes or until the kale is crispy and the chicken is cooked through.
Serve with remaining honey mustard.