Preheat your grill to medium-high heat (about 400°F).
In a small bowl, mix together the olive oil, garlic powder, onion powder, smoked paprika, salt, and black pepper.
Pat the chicken thighs dry with paper towels and rub the spice mixture all over the chicken, ensuring even coverage.
Place the chicken on the grill, skin side down, and cook for about 5-7 minutes until the skin is crispy and golden brown.
Flip the chicken and brush a generous amount of barbecue sauce on the skin side. Grill for another 5-7 minutes.
Flip the chicken again, brush with more barbecue sauce, and continue grilling for an additional 10-15 minutes, or until the internal temperature reaches 165°F.
Remove the chicken from the grill and let it rest for 5 minutes before serving. Serve with extra barbecue sauce on the side.