Preheat your oven to 400°F and line a large sheet pan with parchment paper.
Peel and dice the sweet potato into half-inch cubes and chop the broccoli into bite-sized florets.
Mince the garlic clove finely.
In a small mixing bowl, whisk together the olive oil, lemon juice, minced garlic, rosemary, thyme, salt, and pepper.
Place the chicken breast, sweet potato cubes, and broccoli florets on the sheet pan.
Drizzle the herb marinade over the chicken and vegetables, tossing thoroughly to ensure an even coating.
Spread the ingredients into a single layer on the pan to ensure even roasting.
Roast for 20 to 25 minutes until the chicken is cooked through and the sweet potatoes are tender and lightly caramelized.
Let the chicken rest for 5 minutes before slicing to serve or portioning into meal prep containers.