Preheat your oven to 400°F (200°C) and line a large rimmed baking sheet with parchment paper for easy cleanup.
Prepare the vegetables by dicing the sweet potato into half-inch cubes and slicing the carrots and bell peppers into bite-sized pieces.
Place the chicken breast on one side of the prepared baking sheet and arrange the sweet potatoes, broccoli, carrots, and peppers on the other side.
Drizzle the olive oil over the chicken and the vegetable medley.
Evenly sprinkle the dried oregano, garlic powder, sea salt, and black pepper over all the ingredients on the pan.
Use your hands or tongs to toss the vegetables until coated and rub the seasoning into both sides of the chicken breast.
Roast in the oven for 20 to 25 minutes, or until the chicken reaches an internal temperature of 165°F and the sweet potatoes are fork-tender.
Remove from the oven and let the chicken rest for 5 minutes before slicing to keep it juicy.
Garnish with freshly chopped parsley and serve immediately, or portion into containers for a high-protein meal prep that stays fresh for three days.