Preheat your oven to 400°F (200°C) and line a large rimmed sheet pan with parchment paper for easy cleanup.
Cut the chicken breast into 1-inch bite-sized pieces and peel and cube the sweet potato into 1/2-inch pieces to ensure even cooking.
In a small bowl, whisk together the extra virgin olive oil, lemon juice, lemon zest, dried oregano, garlic powder, sea salt, and black pepper.
Place the chicken, sweet potato cubes, and broccoli florets onto the prepared sheet pan.
Pour the lemon-herb marinade over the chicken and vegetables, tossing thoroughly with your hands or tongs to ensure every piece is well-coated.
Spread the ingredients out into a single layer, ensuring they aren't overcrowded so they 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 let cool slightly before dividing into meal prep containers for the week.