Preheat the oven to 400°F (200°C).
In a small bowl, whisk together the maple syrup, Dijon mustard, olive oil, garlic powder, salt, and pepper.
Place the chicken breasts in a large bowl and pour the marinade over them. Allow to marinate for at least 15 minutes.
While the chicken marinates, prepare the sweet potatoes. Toss the cubed sweet potatoes in olive oil, salt, and thyme, then spread them on a baking sheet.
Transfer the baking sheet with sweet potatoes to the preheated oven.
After 15 minutes, add the marinated chicken breasts to the baking sheet with the sweet potatoes.
Bake for 25-30 minutes, or until the chicken is cooked through and the sweet potatoes are tender.
Remove from the oven and let rest for 5 minutes before serving.
Serve the Maple Dijon Chicken alongside the roasted sweet potatoes, garnished with additional thyme as desired.
