In a mixing bowl, combine the olive oil, soy sauce, honey, apple cider vinegar, minced garlic, smoked paprika, dried oregano, black pepper, salt, and red pepper flakes (if using). Whisk together until well blended. This will create a cohesive marinade that infuses the chicken with flavor.

Place the chicken thighs in a zip-top bag or a shallow dish. Pour the marinade over the chicken, ensuring all pieces are well coated. Seal the bag or cover the dish with plastic wrap.

Refrigerate for at least 1 hour, or up to 8 hours for maximum flavor. Marinating helps to tenderize the meat and allows the flavors to penetrate.

Preheat your grill to medium-high heat (about 400°F or 200°C). This temperature is ideal for grilling chicken thighs, allowing them to cook through without burning.

Remove the chicken from the marinade and let any excess drip off. Discard the marinade.

Place the chicken thighs skin-side down on the grill. Grill for about 6-7 minutes, then flip and grill for another 6-7 minutes, or until the internal temperature reaches 165°F (75°C). This ensures the chicken is cooked through and safe to eat.

Let the chicken rest for 5 minutes before serving. Resting allows the juices to redistribute, keeping the chicken moist.