Preheat your oven to 400°F (200°C) and line a large rimmed baking sheet with parchment paper for easy cleanup.
Cut the chicken breast into 1-inch bite-sized pieces and place them into a large mixing bowl.
Add the broccoli florets, cubed sweet potato, sliced red bell pepper, and sliced zucchini to the bowl with the chicken.
Drizzle the extra virgin olive oil over the mixture, then sprinkle with the dried oregano, garlic powder, sea salt, and black pepper.
Toss everything thoroughly with your hands or a large spoon until the chicken and vegetables are evenly coated in the oil and spices.
Spread the mixture in a single layer on the prepared baking sheet, ensuring the pieces are not overcrowded to allow for proper roasting.
Roast for 20-25 minutes, or until the chicken is cooked through and the sweet potatoes are tender when pierced with a fork.
Remove from the oven and immediately squeeze the fresh lemon juice over the hot chicken and vegetables to brighten the flavors before serving.