Preheat your oven to 400°F (200°C) and line a large rimmed baking sheet with parchment paper.
Wash and peel the carrots, then dice both the carrots and the sweet potato into uniform 1-inch cubes.
Finely mince the garlic cloves.
In a large mixing bowl, combine the chicken breast, cubed sweet potato, and carrots.
Add the olive oil, minced garlic, dried rosemary, dried thyme, sea salt, and black pepper to the bowl.
Toss all ingredients together until the chicken and vegetables are thoroughly and evenly coated in the oil and spices.
Spread the mixture onto the prepared baking sheet in a single layer, ensuring the pieces are not overcrowded to allow for even browning.
Roast for 25 to 30 minutes, or until the chicken is cooked through and the root vegetables are tender and slightly caramelized.