01 - Pat the chicken thighs dry with paper towels to remove excess moisture for better seasoning adhesion.
02 - In a large bowl, whisk together olive oil, apple cider vinegar, brown sugar, smoked paprika, garlic powder, onion powder, chili powder, salt, and black pepper until well combined.
03 - Add chicken thighs to the bowl and toss thoroughly to coat evenly with the seasoning mixture. Let marinate for at least 15 minutes, or up to 4 hours in the refrigerator for deeper flavor penetration.
04 - Preheat grill to medium-high heat (approximately 375-400°F) or preheat oven to 400°F if baking indoors.
05 - Place chicken thighs on the grill skin-side down. Grill for 6-7 minutes until skin begins to crisp. Flip and brush generously with BBQ sauce. Continue grilling for 25-30 minutes, turning and basting with additional BBQ sauce every 5-7 minutes, until internal temperature reaches 175°F and meat is cooked through with slight charring.
06 - For oven preparation, arrange marinated chicken thighs on a foil-lined baking sheet, skin-side up. Roast at 400°F for 30-35 minutes, brushing with BBQ sauce every 10 minutes, until internal temperature reaches 175°F and skin is caramelized.
07 - Remove chicken from heat and let rest for 5 minutes to allow juices to redistribute. Serve with additional BBQ sauce on the side if desired.