Preheat your oven to 400°F (200°C) and line a large baking sheet with parchment paper.
Mince the garlic cloves and combine them in a small bowl with the extra virgin olive oil, rosemary, thyme, sea salt, and black pepper.
Peel the sweet potato and cut it into uniform 1-inch cubes.
Place the chicken breast and the sweet potato cubes on the prepared baking sheet.
Brush half of the garlic-herb oil over the chicken breast and toss the sweet potato cubes in the remaining oil until evenly coated.
Roast in the center of the oven for 20 to 25 minutes, or until the chicken reaches an internal temperature of 165°F and the potatoes are tender.
While the chicken roasts, steam the broccoli florets in a steamer basket over boiling water for 5 minutes until they are bright green and tender-crisp.
Remove the tray from the oven, let the chicken rest for 5 minutes, then serve with the roasted potatoes and steamed broccoli, finishing everything with a fresh squeeze of lemon juice.