Preheat your oven to 400°F (200°C) and line a large baking sheet with parchment paper.
Wash the potato and cut it into 1-inch cubes, then cut the chicken breast into similar 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 potatoes on the prepared baking sheet and pour the marinade over them, tossing well to ensure every piece is evenly coated.
Spread the mixture into a single layer and roast in the oven for 15 minutes.
Remove the pan, add the broccoli florets to the sheet, toss slightly, and roast for an additional 10 to 12 minutes until the chicken is cooked through and the potatoes are tender.
Serve immediately, drizzling any remaining juices from the pan over the chicken.