Preheat your oven to 400°F (200°C) and line a large rimmed baking sheet with parchment paper for easy cleanup.
Peel and dice the sweet potato into 1-inch cubes and slice the carrots into 1/2-inch thick rounds.
Mince the garlic clove finely.
In a large mixing bowl, combine the chicken breast, sweet potato cubes, sliced carrots, and minced garlic.
Drizzle with the olive oil and sprinkle the dried rosemary, dried thyme, sea salt, and black pepper over the top.
Toss everything together until the chicken and vegetables are thoroughly and evenly coated in the oil and herbs.
Spread the mixture in a single layer on the prepared baking sheet, ensuring the chicken pieces aren't overcrowded.
Roast in the center of the oven for 20 to 25 minutes, or until the chicken reaches an internal temperature of 165°F and the vegetables are tender and lightly browned.
Remove from the oven and let the chicken rest for 5 minutes before slicing to ensure it stays juicy.
Serve the sliced chicken alongside the roasted root vegetables.