Preheat your oven to 400°F and line a large rimmed baking sheet with parchment paper for easy cleanup.
Cut the chicken breast into 1-inch cubes and chop the broccoli, bell pepper, and zucchini into uniform bite-sized pieces.
In a small bowl, whisk together the extra virgin olive oil, lemon juice, dried oregano, garlic powder, sea salt, and black pepper.
Place the chicken and vegetables in a large mixing bowl and pour the lemon-herb dressing over them, tossing thoroughly to coat every piece.
Spread the mixture in a single layer on the prepared baking sheet, ensuring enough space for the vegetables to roast rather than steam.
Roast for 20 to 22 minutes, or until the chicken reaches an internal temperature of 165°F and the vegetables are tender with slightly charred edges.
Remove from the oven and serve warm, perhaps with a final squeeze of fresh lemon for extra brightness.