Preheat your oven to 400°F (200°C) and line a large baking sheet with parchment paper for easy cleanup.
Scrub the potato and cut it into 1-inch cubes, then slice the carrots into rounds and break the broccoli into bite-sized florets.
In a large bowl, toss the potatoes, carrots, and broccoli with half of the olive oil, sea salt, and black pepper.
Place the chicken breast on the prepared baking sheet and rub with the remaining olive oil, rosemary, thyme, and garlic powder.
Arrange the seasoned vegetables in a single layer around the chicken breast on the baking sheet.
Roast for 20 to 25 minutes, or until the chicken reaches an internal temperature of 165°F and the potatoes are fork-tender.
Let the chicken rest for 5 minutes before slicing to ensure the juices stay locked in for a moist finish.