In a mixing bowl, combine gochujang, honey, soy sauce, sesame oil, minced garlic, and grated ginger. Mix well to create the marinade.
Season the chicken thighs with salt and pepper. Place them in a resealable plastic bag or a shallow dish.
Pour the marinade over the chicken, ensuring all pieces are well-coated. Seal the bag or cover the dish, and refrigerate for at least 30 minutes (or up to 2 hours for more flavor).
Preheat your grill or a grill pan over medium-high heat.
Remove the chicken from the marinade, allowing any excess marinade to drip off. Discard the leftover marinade.
Grill the chicken thighs for about 6-7 minutes on each side, or until the internal temperature reaches 165°F (75°C) and they are nicely charred.
Once cooked, let the chicken rest for 5 minutes, then slice into strips.
Garnish with chopped green onions and sprinkle sesame seeds over the top before serving.
Notes
For more flavor, marinate the chicken for up to 2 hours.