Preheat your oven to 400°F (200°C) and line a large rimmed baking sheet with parchment paper.
Peel the sweet potato and carrots, then dice them into uniform 1/2-inch cubes to ensure they roast evenly.
Mince the garlic cloves and finely chop the fresh rosemary and thyme leaves.
In a large mixing bowl, combine the chicken breast, diced sweet potatoes, and carrots.
Drizzle the olive oil over the mixture, then add the minced garlic, chopped herbs, sea salt, and black pepper.
Toss everything thoroughly until the chicken and vegetables are well-coated in the oil and seasonings.
Spread the mixture in a single layer on the prepared baking sheet, ensuring the pieces aren't overcrowded.
Roast for 20 to 25 minutes, or until the chicken reaches an internal temperature of 165°F and the vegetables are tender and slightly browned.
Remove from the oven and let the chicken rest for 5 minutes before slicing to maintain its juiciness.