Preheat the oven to 400°F (200°C).
In a mixing bowl, combine the barbecue sauce, brown sugar, olive oil, garlic powder, onion powder, salt, and black pepper. Whisk well to create a marinade.
Pat the chicken thighs dry with paper towels to ensure crispy skin.
In the baking dish, place the chicken thighs skin side up. Pour half of the barbecue marinade over the chicken, ensuring each piece is well coated. Reserve the remaining marinade for later.
Bake the chicken in the preheated oven for 25 minutes.
After 25 minutes, remove the chicken from the oven and brush with the reserved barbecue marinade.
Return the chicken to the oven and bake for an additional 15 minutes, or until the internal temperature reaches 165°F (75°C) and the skin is caramelized.
Let the chicken rest for 5 minutes before serving to help the juices redistribute.