Preheat your oven to 400°F (200°C) and line a large rimmed baking sheet with parchment paper for easy cleanup.
Dice the chicken breast and sweet potato into uniform 1-inch cubes to ensure even cooking.
Chop the red bell pepper into 1-inch pieces and break the broccoli into bite-sized florets.
In a large mixing bowl, whisk together the extra virgin olive oil, lemon juice, dried oregano, garlic powder, sea salt, and black pepper.
Add the chicken and all the vegetables to the bowl, tossing thoroughly until every piece is coated in the herb marinade.
Spread the mixture in a single layer across the prepared sheet pan, ensuring nothing is overcrowded so the veggies roast rather than steam.
Bake for 20-25 minutes, or until the chicken reaches an internal temperature of 165°F and the sweet potatoes are fork-tender.
Remove from the oven and garnish with freshly chopped parsley before serving or portioning into containers for meal prep.