Preheat your oven to 400°F (200°C) and line a large rimmed baking sheet with parchment paper for easy cleanup.
Dice the chicken breast, sweet potato, and red bell pepper into uniform 1-inch cubes, and break the broccoli into bite-sized florets.
In a large mixing bowl, whisk together the extra virgin olive oil, lemon juice, dried oregano, garlic powder, sea salt, and black pepper.
Add the diced chicken and all the chopped vegetables to the bowl, tossing thoroughly until every piece is evenly coated in the herb oil.
Spread the mixture in a single, even layer across the prepared baking sheet, ensuring there is enough space for the air to circulate.
Roast for 20 to 25 minutes, tossing the ingredients halfway through, until the chicken is cooked through and the vegetables are tender with golden, charred edges.