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 chop the broccoli, bell pepper, and zucchini into uniform chunks to ensure even cooking.
In a small mixing bowl, whisk together the extra virgin olive oil, fresh lemon juice, dried oregano, garlic powder, sea salt, and black pepper.
Place the chicken pieces and chopped vegetables onto the prepared sheet pan.
Drizzle the lemon-herb oil mixture over the chicken and vegetables, then toss thoroughly with tongs or clean hands to coat every piece.
Spread the ingredients out into a single layer, ensuring they aren't overcrowded so they roast rather than steam.
Roast in the center of the oven for 18 to 22 minutes, or until the chicken is cooked through and the vegetables are tender with slightly caramelized edges.
Remove from the oven and let rest for 2 minutes before serving.