Preheat your oven to 400°F (200°C) and line a large sheet pan with parchment paper for easy cleanup.
Peel and chop the carrots and parsnips into 1-inch chunks, and slice 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.
Pat the chicken breast dry with a paper towel and place it in the center of the prepared sheet pan.
Place the chopped vegetables in a mixing bowl and toss with two-thirds of the garlic-herb oil until thoroughly coated.
Spread the vegetables in a single layer around the chicken breast on the sheet pan, ensuring they aren't overcrowded.
Brush the remaining herb oil over the top of the chicken breast.
Roast for 25 to 30 minutes, or until the chicken reaches an internal temperature of 165°F and the root vegetables are tender and caramelized.
Remove from the oven and let the chicken rest for 5 minutes before slicing to keep it juicy.