Preheat your oven to 400°F and line a large sheet pan with parchment paper for easy cleanup.
Dice the sweet potato into 1-inch cubes, slice the carrot into rounds, and halve the Brussels sprouts.
Mince the garlic cloves and finely chop the fresh rosemary and thyme leaves.
In a large bowl, toss the prepared vegetables and garlic with half of the avocado oil, sea salt, black pepper, and chopped herbs.
Rub the chicken breast with the remaining avocado oil and season both sides evenly with the rest of the salt, pepper, and herbs.
Spread the vegetables in a single layer on the sheet pan and nestle the chicken breast in the center.
Roast for 20 to 25 minutes until the chicken reaches an internal temperature of 165°F and the vegetables are tender and golden.
Allow the chicken to rest for 5 minutes before slicing to ensure it stays juicy and flavorful.