Preheat your oven to 400°F and line a large sheet pan with parchment paper for easy cleanup.
Slice the baby potatoes into halves, the carrots into rounds, and the red onion into wedges.
Mince the garlic cloves finely.
In a large bowl, toss the potatoes, carrots, and onions with 1 tablespoon of olive oil, half the rosemary, half the thyme, the sea salt, and the black pepper.
Spread the vegetables in a single layer on the prepared sheet pan and roast for 15 minutes.
While the vegetables are roasting, rub the chicken breast with the remaining olive oil, minced garlic, and the rest of the dried herbs.
Move the vegetables to the sides of the pan and place the chicken breast and broccoli florets in the center.
Return the pan to the oven and roast for an additional 20 to 25 minutes, or until the chicken reaches an internal temperature of 165°F.
Remove from the oven and let the chicken rest for 5 minutes to lock in the juices before slicing and serving.