Step 1: Prepare the Marinade

1. In a large mixing bowl, whisk together the soy sauce, garlic, ginger, sesame oil, honey (or brown sugar), rice vinegar (or lime juice), chili flakes or Sriracha (if using), and black pepper. Adjust the sweetness or saltiness as needed.
2. If the marinade feels too thick, add 1-2 tablespoons of water to achieve the desired consistency.

Step 2: Marinate the Chicken

1. Pat the chicken pieces dry with a paper towel to help the marinade stick.
2. Place the chicken in a sealable plastic bag or a shallow dish and pour the marinade over it.
3. Ensure all the chicken pieces are evenly coated. Seal the bag (or cover the dish) and refrigerate for at least 2 hours, ideally overnight, for deeper flavor.

Step 3: Preheat the Grill

1. Preheat your grill to medium-high heat (about 375-400°F). Clean the grates thoroughly and lightly oil them to prevent sticking.
2. If using a charcoal grill, create a two-zone setup with coals on one side for direct and indirect cooking.

Step 4: Grill the Chicken

1. Remove the chicken from the marinade and let any excess drip off. Discard the used marinade, or boil it separately for basting.
2. Place the chicken on the grill over direct heat. Grill for 3-4 minutes per side, or until you get nice char marks.
3. Move the chicken to indirect heat, cover, and cook until the internal temperature reaches 165°F (74°C), about 6-10 more minutes, depending on the thickness.

Step 5: Rest the Chicken

1. Remove the chicken from the grill and let it rest on a plate for 5 minutes. This allows the juices to redistribute, keeping the chicken tender and moist.

Step 6: Garnish and Serve

1. Sprinkle the grilled chicken with toasted sesame seeds and chopped cilantro for added flavor and visual appeal.
2. Serve with lime wedges on the side for a fresh, zesty touch.