Preheat your oven to 400°F (200°C) and line a large baking sheet with parchment paper.
Dice the sweet potato, carrots, and chicken breast into uniform 1-inch pieces to ensure even cooking.
Mince the garlic cloves and finely chop the fresh rosemary leaves.
In a large mixing bowl, combine the chicken, sweet potatoes, and carrots.
Drizzle with extra virgin olive oil and add the minced garlic, rosemary, sea salt, black pepper, and onion powder.
Toss everything thoroughly until the chicken and vegetables are evenly coated with 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 chicken is cooked through and the vegetables are tender and golden brown.