Preheat the oven to 400°F and line a large baking sheet with parchment paper for easy cleanup.
Peel and dice the sweet potato and carrots into uniform 1-inch pieces to ensure even roasting.
Finely mince the garlic clove.
In a large mixing bowl, combine the chicken breast, sweet potatoes, and carrots, then drizzle with olive oil.
Sprinkle the dried rosemary, thyme, sea salt, and black pepper over the mixture and toss until everything is well coated.
Spread the ingredients in a single layer on the prepared baking sheet, ensuring the chicken is not crowded by the vegetables.
Roast for 25 to 30 minutes, or until the chicken is cooked through and the vegetables are tender with golden edges.
Remove from the oven and let the chicken rest for 5 minutes before serving to maintain its moisture.