Preheat your oven to 400°F (200°C) and line a large rimmed baking sheet with parchment paper.
Peel and slice the carrots and parsnips into half-inch rounds, and cut the red onion into thick wedges.
In a large mixing bowl, whisk together the extra virgin olive oil, minced garlic, chopped rosemary, thyme, sea salt, and black pepper.
Add the chicken breast and the prepared vegetables to the bowl, tossing thoroughly until every piece is coated in the herb oil.
Spread the chicken and vegetables in a single layer on the prepared baking sheet, ensuring the pieces are not overlapping.
Roast for 20 to 25 minutes, or until the chicken reaches an internal temperature of 165°F and the vegetables are fork-tender and golden.
Remove from the oven and allow the chicken to rest for 5 minutes before slicing to ensure it remains juicy and tender.