Preheat your oven to 400°F and line a large rimmed baking sheet with parchment paper for easy cleanup.
Peel the sweet potato and cut it into 1/2-inch cubes, then slice the carrots into 1/4-inch thick rounds.
In a small mixing bowl, whisk together the olive oil, lemon juice, lemon zest, minced garlic, chopped rosemary, and chopped thyme.
Place the chicken breast and the prepared vegetables onto the baking sheet in a single layer.
Drizzle the lemon-herb oil over the chicken and vegetables, then sprinkle everything with sea salt and black pepper.
Toss the vegetables with your hands or tongs to ensure they are evenly coated in the oil and seasonings.
Roast for 20 to 25 minutes, or until the chicken reaches an internal temperature of 165°F and the vegetables are tender and slightly caramelized.
Remove from the oven and let the chicken rest for 5 minutes before slicing to keep it juicy.