Start by patting the chicken thighs dry with paper towels to ensure they achieve a nice caramelization. In a bowl, whisk together soy sauce, brown sugar, sesame oil, rice vinegar, minced garlic, grated ginger, gochujang, garlic powder, and black pepper until fully combined. Coat each chicken thigh generously with the marinade, then cover and refrigerate for at least 30 minutes. For maximum flavor, marinating for several hours is recommended.

Choose your cooking method—skillet, grill, or oven. If using a skillet, heat 1-2 tablespoons of oil in a large non-stick skillet over medium-high heat until it shimmers. Ensure that your cooking surface is ready before adding the chicken.

Remove the chicken thighs from the marinade, allowing any excess to drip off to prevent sogginess. Place the thighs in the hot skillet, cooking for 5-6 minutes on each side until nicely browned and caramelized; aim for an internal temperature of 165°F.

While the chicken is cooking, pour the reserved marinade into a small saucepan. Bring it to a gentle simmer over medium heat, allowing it to reduce and thicken for about 5-7 minutes to create a glaze.

During the final few minutes of cooking, brush the thickened glaze generously over the chicken thighs to enhance the flavor.

Once the chicken has finished cooking, transfer it to a plate and let it rest for about 5 minutes. Slice the chicken, garnish with green onions and sesame seeds, and serve hot with extra glaze.