Preheat your oven to 400°F (200°C) and line a large rimmed baking sheet with parchment paper for easy cleanup.
In a small mixing bowl, whisk together the extra virgin olive oil, lemon juice, lemon zest, rosemary, thyme, garlic powder, sea salt, and black pepper.
Peel and cut the sweet potato into 1/2-inch cubes, then place them on one side of the prepared baking sheet.
Place the chicken breast in the center of the sheet and arrange the broccoli florets on the remaining open space.
Drizzle the lemon-herb oil mixture over the chicken and vegetables, using your hands or a brush to ensure the chicken is fully coated and the vegetables are tossed evenly.
Roast in the center of the oven for 20 to 25 minutes, or until the chicken reaches an internal temperature of 165°F and the sweet potatoes are fork-tender.
Remove from the oven and let the chicken rest for 5 minutes before slicing to ensure the juices stay locked in.