Pat the boneless skinless chicken thighs dry with paper towels and season with kosher salt and freshly ground black pepper.

Set aside half of your BBQ sauce in a separate bowl. In the large bowl with the chicken, combine the remaining BBQ sauce with olive oil and water.

Pour the marinade over the chicken, ensuring every piece is well-coated. Let it marinate for at least 30 minutes, ideally up to 2 hours.

Preheat your grill to medium temperature (about 350°F to 375°F) and oil the grill grates to prevent sticking.

Place the marinated chicken thighs on the grill, close the lid, and cook for about 3-4 minutes, then flip and grill for another 4 minutes.

Baste both sides of the chicken with the reserved BBQ sauce and grill for an additional 3-4 minutes, checking for doneness with a meat thermometer.

Remove the chicken from the grill and let it rest for 2-3 minutes before serving with the remaining BBQ sauce.