Preheat your oven to 400°F (200°C) and line a large rimmed baking sheet with parchment paper.
Prepare the vegetables by halving the Brussels sprouts, peeling and cubing the sweet potato into half-inch pieces, and slicing the carrot into rounds.
Pat the chicken breast dry with a paper towel to ensure the herbs stick and the skin gets a nice golden color.
In a small bowl, whisk together the olive oil, dried rosemary, dried thyme, garlic powder, sea salt, and black pepper.
Place the chicken and all the prepared vegetables onto the baking sheet, then drizzle with the herb oil mixture.
Toss the vegetables to coat thoroughly and rub the remaining oil over both sides of the chicken breast.
Spread the ingredients out in a single layer, ensuring the chicken is not crowded by the vegetables.
Roast for 20 to 25 minutes, or until the chicken reaches an internal temperature of 165°F and the vegetables are fork-tender and lightly browned.
Remove from the oven and let the chicken rest for 5 minutes before slicing to keep it juicy.
Serve the sliced chicken alongside the roasted vegetables for a complete, clean-eating meal.