Preheat your oven to 400°F and line a large rimmed baking sheet with parchment paper for easy cleanup.
Peel and dice the sweet potato and carrots into uniform 1-inch cubes to ensure they roast evenly.
Mince the garlic clove and finely chop the fresh rosemary and thyme leaves.
In a small mixing bowl, whisk together the olive oil, lemon juice, lemon zest, minced garlic, rosemary, thyme, sea salt, and black pepper.
Place the chicken breast and the prepared root vegetables onto the baking sheet and drizzle the lemon-herb mixture over everything, tossing well to coat.
Spread the ingredients into a single layer and roast for 25 to 30 minutes, or until the chicken reaches an internal temperature of 165°F and the vegetables are tender and caramelized.
Allow the chicken to rest for 5 minutes before slicing to maintain its succulent texture.