Preheat your oven to 400°F (200°C).
Prepare the sweet potatoes by peeling and cubing them. Then toss them with olive oil, salt, and pepper.
Spread the sweet potatoes on a baking sheet and roast in the preheated oven for about 15 minutes.
While the sweet potatoes are roasting, prepare the chicken by patting it dry and seasoning with garlic powder, salt, and pepper.
In a separate bowl, mix the maple syrup and olive oil together. Brush this mixture over the chicken thighs.
After 15 minutes, remove the sweet potatoes from the oven and place the seasoned chicken thighs on top of them.
Return the baking sheet to the oven and roast for an additional 30-35 minutes, until the chicken is cooked through and the sweet potatoes are tender.
Garnish with fresh thyme leaves before serving, if desired.