Preheat your oven to 400°F (200°C) and line a large sheet pan with parchment paper for easy cleanup.
Peel the sweet potato and cut into 1/2-inch cubes; slice the carrots into rounds and chop the bell pepper into bite-sized pieces.
Place the chicken breast in the center of the sheet pan and surround it with the sweet potatoes, broccoli, carrots, and bell peppers.
Drizzle the olive oil evenly over the chicken and the vegetable medley.
In a small bowl, mix the rosemary, thyme, garlic powder, sea salt, and black pepper.
Sprinkle the herb seasoning over everything on the pan, tossing the vegetables and flipping the chicken to ensure a thorough coating.
Spread the ingredients out into a single layer to ensure even roasting and caramelization.
Roast 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 5 minutes before slicing to retain its natural juices.