Preheat your oven to 400°F (200°C) and line a large rimmed baking sheet with parchment paper.
Peel the carrots and parsnip, then slice them into 1-inch thick rounds or bite-sized chunks.
Mince the garlic cloves and finely chop the fresh rosemary and thyme leaves.
In a mixing bowl, toss the chopped root vegetables with half of the olive oil, half of the minced garlic, and a pinch of the salt and pepper.
Pat the chicken breast dry with a paper towel and place it on the prepared baking sheet.
Rub the chicken with the remaining olive oil, garlic, rosemary, thyme, salt, and pepper until evenly coated.
Spread the seasoned root vegetables in a single layer around the chicken on the baking sheet.
Roast for 20-25 minutes, or until the chicken reaches an internal temperature of 165°F and the vegetables are tender and golden brown.
Remove from the oven and let the chicken rest for 5 minutes before slicing to ensure it remains juicy, then serve alongside the roasted vegetables.