In a medium bowl, combine gochujang, honey, soy sauce, sesame oil, minced garlic, grated ginger, salt, and pepper. Stir well until it forms a smooth marinade. Add the chicken into the bowl and coat it thoroughly with the mixture. Let it marinate for at least 10 minutes at room temperature, or for an enhanced flavor, refrigerate for up to 2 hours.

Place a large skillet over medium-high heat and add 1 tablespoon of vegetable oil. Allow the oil to heat until it shimmers and easily coats the bottom of the pan.

Once the oil is hot, add the sliced onion and bell pepper to the skillet. Sauté for about 3-4 minutes, stirring occasionally, until the vegetables are softened and slightly caramelized. Remove the veggies from the skillet and set them aside on a plate.

In the same skillet, add the marinated chicken pieces in a single layer. Cook for 5-7 minutes, turning occasionally until the chicken is browned and cooked through.

Reduce the heat to medium and return the sautéed onion and bell pepper to the skillet, mixing them gently with the cooked chicken. Let them cook together for an additional 2-3 minutes.

Remove the pan from the heat and sprinkle the cooked Korean Gochujang Chicken generously with chopped green onions and sesame seeds. Serve hot.