Preheat your oven to 400°F (200°C) and line a large baking sheet with parchment paper.
Dice the sweet potato into small half-inch cubes and chop the broccoli into bite-sized florets.
Mince the garlic and zest the half lemon into a small bowl.
In a large mixing bowl, combine the chicken breast, sweet potato cubes, and broccoli florets.
Drizzle with olive oil and add the minced garlic, lemon zest, rosemary, thyme, sea salt, and black pepper.
Toss everything thoroughly until the chicken and vegetables are evenly coated in the oil and seasonings.
Spread the mixture in a single layer on the prepared baking sheet, ensuring the chicken pieces aren't crowded.
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 squeeze the fresh lemon juice over the entire tray before serving.