Preheat your oven to 400°F (200°C) and line a large rimmed baking sheet with parchment paper.
Peel the carrots and parsnips, then slice them into 1-inch rounds; peel and roughly chop the red onion.
Mince the garlic cloves and finely chop the fresh rosemary and thyme leaves.
In a large mixing bowl, combine the chicken breast, carrots, parsnips, and onion.
Drizzle with extra virgin olive oil and sprinkle with the minced garlic, rosemary, thyme, sea salt, and black pepper.
Toss everything thoroughly until the chicken and vegetables are evenly coated in the oil and herbs.
Spread the mixture onto the prepared baking sheet in a single layer, ensuring the chicken is in the center.
Roast for 20 to 25 minutes, or until the chicken reaches an internal temperature of 165°F and the root vegetables are tender and slightly browned.
Remove from the oven and let the chicken rest for 5 minutes before slicing to ensure it remains juicy.