Begin by preparing the chicken: In a mixing bowl, combine the chicken pieces with vinegar, minced garlic, grated ginger, salt, and pepper. Toss everything together until the chicken is evenly coated and let it marinate for 20 to 30 minutes.
Next, create the flavorful sauce: In a saucepan over medium heat, mix honey, vinegar, brown sugar, gochujang, soy sauce, minced garlic, grated ginger, and black pepper. Stir continuously until the mixture reaches a gentle boil, then lower the heat and let it simmer for 3 to 4 minutes before removing it from the stove.
In a deep fryer, pour in about 1 inch of oil and heat it to 350°F (175°C).
While the oil heats up, place cornstarch in a separate bowl. Take the marinated chicken and coat each piece thoroughly with the cornstarch.
Fry the chicken in small batches, ensuring not to overcrowd the fryer. Cook each piece until it turns a light golden brown, which should take about 2 minutes per side.
Once the chicken is fried, reheat the oil to the same temperature of 350°F (175°C) and deep-fry the chicken again for an additional 40 seconds, until it achieves a deep golden brown color. Then, transfer the crispy chicken into the prepared sauce.
Gently heat the sauce and chicken together over medium-low heat for about 3 minutes, allowing the chicken to absorb the delicious flavors.