Preheat your oven to 400°F (200°C) and line a large baking sheet with parchment paper for easy cleanup.
Peel the sweet potato and carrots, then dice them into 1-inch cubes; cut the broccoli into bite-sized florets.
Pat the chicken breast dry with a paper towel and slice it into even 1-inch strips to ensure quick and even cooking.
In a large mixing bowl, combine the chicken, sweet potatoes, carrots, and broccoli.
Mince the garlic and add it to the bowl along with the olive oil, rosemary, thyme, sea salt, and black pepper.
Toss everything thoroughly until the chicken and vegetables are evenly coated in the oil and herb mixture.
Spread the mixture in a single layer on the prepared baking sheet, ensuring nothing is overcrowded so the vegetables can caramelize.
Roast in the center of 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 2 minutes before serving to keep it juicy.