Preheat your oven to 400°F (200°C) and line a large baking sheet with parchment paper.
Wash and halve the baby potatoes, slice the carrots into rounds, and cut the red onion into thick wedges.
In a large bowl, toss the potatoes, carrots, and red onion with 1 teaspoon of olive oil and half of the salt, pepper, rosemary, and thyme.
Spread the vegetables onto the baking sheet in a single layer, leaving space for the chicken breast.
Rub the chicken breast with the remaining teaspoon of olive oil, minced garlic, and the rest of the herbs and seasoning.
Place the chicken on the baking sheet and roast for 15 minutes.
Add the broccoli florets to the sheet, tossing them quickly with the other vegetables, and roast for another 10 to 15 minutes until the chicken reaches an internal temperature of 165°F.
Let the chicken rest for 5 minutes before slicing to ensure the meat stays juicy and tender.