Pat dry chicken thighs thoroughly with paper towels.
Place chicken in a bowl, drizzle with olive oil and sprinkle with salt, pepper, and rosemary. Add optional seasonings if using. Massage to coat evenly.
Let chicken rest at room temperature for 15-20 minutes.
Preheat grill to medium-high heat (375-400°F). Create a two-zone fire with direct and indirect heat areas.
Oil the grill grates to prevent sticking.
Place chicken skin-side down on direct heat and grill for 5 minutes until skin crisps and develops grill marks.
Flip chicken and move to indirect heat. Close lid and cook for 5 minutes.
Brush half of the barbecue sauce on chicken. Close lid and cook for 3-4 minutes.
Flip chicken, brush with remaining sauce, and grill for final 3-4 minutes until internal temperature reaches 165°F.
Remove from grill and let rest for 5 minutes before serving.
Notes
For best results, apply barbecue sauce only during the last few minutes of grilling to prevent burning.
Bone-in, skin-on thighs are recommended for juicier results, but boneless thighs or chicken breasts can be substituted with adjusted cooking times.
Nutrition facts are estimates and may vary based on ingredients used, portion sizes, and preparation methods.