Preheat your oven to 400°F (200°C) and line a large baking sheet with parchment paper.
Peel and dice the sweet potato into small 1/2-inch cubes to ensure they cook evenly with the chicken.
In a large mixing bowl, whisk together the olive oil, lemon juice, dried oregano, garlic powder, sea salt, and black pepper.
Add the chicken breast, sweet potato cubes, and broccoli florets to the bowl, tossing thoroughly until everything is well-coated in the herb oil.
Spread the mixture in a single layer on the prepared baking sheet, ensuring the chicken and vegetables are not overcrowded.
Roast for 20 to 25 minutes, or until the chicken reaches an internal temperature of 165°F and the sweet potatoes are golden and tender.
Remove from the oven and garnish with freshly chopped parsley before serving.