Preheat your oven to 400°F (200°C) and line a large rimmed baking sheet with parchment paper to ensure easy cleanup and prevent sticking.
Dice the sweet potato into half-inch cubes and slice the carrots into thin rounds so they roast at the same rate as the chicken.
Cut the chicken breast into bite-sized pieces and place them in a large mixing bowl along with the sweet potato, carrots, and broccoli florets.
In a small bowl, whisk together the olive oil, minced garlic, dried rosemary, dried thyme, sea salt, and black pepper until well combined.
Pour the herb oil over the chicken and vegetables, tossing thoroughly with your hands or a spatula to ensure every piece is evenly coated.
Spread the mixture in a single layer on the prepared baking sheet, making sure not to overcrowd the pan so the vegetables roast rather than steam.
Roast for 20 to 25 minutes, tossing the ingredients halfway through, until the chicken is cooked through and the vegetables are golden and tender.