Preheat your oven to 400°F and line a large baking sheet with parchment paper for easy cleanup.
Peel and dice the sweet potato and parsnip into 1-inch cubes, and slice the carrots into 1/2-inch rounds.
Cut the chicken breast into 1-inch bite-sized pieces to ensure they cook at the same rate as the vegetables.
In a large mixing bowl, combine the chicken pieces, diced sweet potato, parsnip, and carrots.
Drizzle the olive oil over the mixture and sprinkle with the dried rosemary, garlic powder, sea salt, and black pepper.
Toss the ingredients until everything is evenly coated in the oil and seasonings.
Spread the mixture in a single layer on the prepared baking sheet, ensuring the pieces are not overcrowded.
Roast for 25-30 minutes, tossing halfway through, until the vegetables are tender and the chicken is cooked through with a golden-brown exterior.