Preheat your oven to 400°F and line a large rimmed baking sheet with parchment paper to prevent sticking and ensure easy cleanup.
Peel the sweet potato and the carrots, then dice them into uniform 1-inch cubes so they roast at the same rate as the chicken breast.
In a large mixing bowl, combine the chicken breast, diced sweet potato, and carrots with olive oil, minced garlic, rosemary, thyme, salt, and pepper.
Toss the ingredients thoroughly until every piece of chicken and vegetable is evenly coated with the aromatic herb oil.
Spread the mixture onto the prepared baking sheet in a single layer, making sure not to overcrowd the pan so the vegetables can properly caramelize.
Roast for 25 to 30 minutes, or until the chicken reaches an internal temperature of 165°F and the root vegetables are tender and golden brown.
Remove from the oven and allow the chicken to rest for at least 5 minutes before slicing to ensure the meat stays succulent and juicy.