Preheat your oven to 400°F (200°C) and line a large baking sheet with parchment paper.
Peel and chop the carrots, parsnips, and sweet potato into uniform 1-inch cubes for even roasting.
In a large mixing bowl, toss the cubed vegetables with half of the olive oil, half of the minced garlic, and half of the fresh herbs.
Spread the seasoned vegetables in a single layer across the prepared baking sheet.
Pat the chicken breast dry and rub with the remaining olive oil, garlic, herbs, sea salt, and black pepper.
Nestle the chicken breast onto the baking sheet among the vegetables.
Roast in the oven for 25 to 30 minutes, or until the chicken reaches an internal temperature of 165°F and the vegetables are tender.
Remove from the oven and let the chicken rest for 5 minutes before slicing to ensure it stays juicy.
Serve the sliced chicken alongside the roasted root vegetables for a complete, clean-eating meal.