Preheat your oven to 400°F and line a large rimmed baking sheet with parchment paper.
Peel and slice the carrots and parsnips into half-inch rounds, and cube the sweet potato into uniform half-inch pieces.
In a large mixing bowl, toss the prepared vegetables with half of the olive oil, half of the minced garlic, and a pinch of salt and pepper.
Place the chicken breast on the baking sheet and rub with the remaining olive oil, garlic, rosemary, thyme, salt, and pepper.
Spread the seasoned root vegetables in a single layer around the chicken on the baking sheet.
Roast for 25 to 30 minutes, or until the chicken reaches an internal temperature of 165°F and the vegetables are fork-tender.
Remove from the oven and let the chicken rest for 5 minutes before slicing to keep it juicy.