Preheat your oven to 400°F and line a large rimmed baking sheet with parchment paper for easy cleanup.
Dice the sweet potato into 1-inch cubes and slice the carrots into 1/2-inch thick rounds to ensure even cooking.
Finely mince the garlic cloves and place them in a large mixing bowl.
Add the sweet potatoes and carrots to the bowl along with half of the olive oil, rosemary, thyme, salt, and pepper, tossing until well coated.
Spread the vegetables in a single layer on the prepared baking sheet, leaving space in the center for the chicken.
Rub the chicken breast with the remaining olive oil and the rest of the garlic and herb mixture.
Place the chicken in the center of the baking sheet nestled among the root vegetables.
Roast for 25 to 30 minutes or until the chicken reaches an internal temperature of 165°F and the vegetables are tender and lightly browned.
Allow the chicken to rest for 5 minutes before slicing to keep the meat succulent and juicy.