In a medium bowl, whisk together the lime juice, maple syrup, 2 tablespoons of vegetable oil, garlic powder, 1 teaspoon of kosher salt, and ½ teaspoon of black pepper until well combined.

Place the chicken thighs in a resealable plastic bag or shallow dish, and pour the prepared marinade over them. Ensure the chicken is evenly coated. Seal the bag (or cover the dish) and refrigerate for at least 1 hour, or up to 24 hours, to allow the flavors to develop fully.

When ready to cook, preheat the oven to 400°F (200°C). Remove the chicken from the refrigerator and let it rest at room temperature for approximately 10 minutes. Line a large baking sheet with parchment paper or aluminum foil for easier cleanup.

Arrange the diced sweet potatoes on the prepared baking sheet. Drizzle with the remaining 2 tablespoons of vegetable oil, and season with the remaining ½ teaspoon of kosher salt and ½ teaspoon of black pepper. Toss lightly to coat the sweet potatoes evenly.

Remove the chicken from the marinade, allowing any excess liquid to drip off, and place the thighs on the baking sheet among the sweet potatoes. Discard any remaining marinade.

Transfer the baking sheet to the preheated oven and roast for 20 to 25 minutes, turning the chicken and sweet potatoes halfway through the cooking time to promote even browning.

The dish is done when the chicken reaches an internal temperature of 165°F (74°C) and the sweet potatoes are tender with lightly caramelized edges.

Remove from the oven and allow the chicken to rest for 5 minutes before serving. Serve warm, directly from the pan, or transfer to a platter for presentation. The sweet glaze formed during roasting may be spooned over the chicken for added flavor.