Preheat your oven to 400°F and line a large rimmed baking sheet with parchment paper.
Peel and dice the sweet potato and carrots into uniform 1-inch cubes, and roughly chop the red onion.
Mince the garlic clove and set aside.
In a large bowl, combine the chicken breast, sweet potato cubes, carrots, and onion.
Add the olive oil, minced garlic, dried rosemary, dried thyme, sea salt, and black pepper to the bowl.
Toss all ingredients together until the chicken and vegetables are evenly coated with the oil and spices.
Spread the mixture in a single layer on the prepared baking sheet, ensuring the chicken is not crowded.
Roast for 25 to 30 minutes, or until the chicken reaches an internal temperature of 165°F and the vegetables are tender.
Let the chicken rest for 5 minutes before slicing and serving alongside the roasted vegetables.