Preheat your oven to 400°F (200°C) and line a large rimmed baking sheet with parchment paper.
Peel and chop the carrots and parsnips into 1-inch chunks, and cut the red onion into thick wedges.
In a small bowl, whisk together the extra virgin olive oil, minced garlic, dried rosemary, dried thyme, sea salt, and black pepper.
Place the chicken breast and the prepared vegetables into a large mixing bowl and pour the herb oil over them.
Toss everything thoroughly with your hands or tongs to ensure every piece is well-coated in the aromatics.
Spread the chicken and vegetables in a single layer on the baking sheet, giving the chicken enough space to roast evenly.
Roast for 25 to 30 minutes, or until the chicken reaches an internal temperature of 165°F and the vegetables are tender and golden.
Let the chicken rest for 5 minutes before slicing to keep it juicy, then serve alongside the roasted root vegetables.