Preheat your oven to 400°F (200°C) and line a large sheet pan with parchment paper for easy cleanup.
Peel and dice the sweet potato into 1/2-inch cubes. Mince the garlic cloves finely.
In a small bowl, whisk together the olive oil, minced garlic, rosemary, thyme, salt, and pepper.
Place the sweet potato cubes on one side of the sheet pan, drizzle with 1/3 of the herb oil mixture, and toss to coat evenly.
Roast the sweet potatoes for 10 minutes, as they take longer to cook than the chicken and broccoli.
While potatoes roast, brush the chicken breast with another 1/3 of the herb oil. Toss the broccoli florets with the remaining oil.
Remove the pan from the oven, add the chicken breast to the center, and arrange the broccoli on the remaining side.
Return the pan to the oven and roast for 15-20 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 to ensure it stays juicy and tender.