Preheat your oven to 400°F (200°C) and line a large rimmed baking sheet with parchment paper.
Peel and dice the sweet potato, carrots, and parsnips into uniform 1-inch cubes to ensure even roasting.
Pat the chicken breast dry with a paper towel and cut into large, bite-sized pieces.
In a large mixing bowl, combine the chicken and chopped root vegetables.
Drizzle with extra virgin olive oil and sprinkle with sea salt, black pepper, garlic powder, and finely chopped fresh rosemary.
Toss everything thoroughly until the chicken and vegetables are well-coated in the oil and spices.
Spread the mixture in a single layer on the prepared baking sheet, ensuring space between pieces for maximum crispiness.
Roast in the center of the oven for 25 to 30 minutes, tossing halfway through, until the chicken is cooked through and the vegetables are tender and golden brown.
Remove from the oven and let rest for 2 minutes before serving warm.