01 - In a large bowl, combine gochujang, soy sauce, sesame oil, honey, rice vinegar, garlic, ginger, brown sugar, and black pepper. Mix thoroughly until the brown sugar dissolves completely and the mixture forms a smooth, uniform glaze.
02 - Add chicken pieces to the bowl, tossing to coat evenly. Cover and marinate for at least 15 minutes, or up to 2 hours in the refrigerator for deeper flavor penetration.
03 - Preheat a large skillet or grill pan over medium-high heat until hot but not smoking.
04 - Shake excess marinade from chicken pieces and arrange in a single layer in the hot pan. Cook for 5 to 7 minutes per side, turning occasionally, until chicken is cooked through and develops a caramelized, charred exterior.
05 - Pour remaining marinade into the pan, reduce heat to medium, and simmer for 2 to 3 minutes while tossing the chicken. The sauce will thicken into a glossy coating that clings to the meat.
06 - Transfer glazed chicken to a serving platter. Sprinkle generously with sliced green onions and sesame seeds. Serve immediately while hot, accompanied by steamed rice.