Cut the chicken thighs into 1-inch chunks and place them in a mixing bowl. Add salt, pepper, Korean red pepper flakes, garlic powder, egg whites, and cornstarch. Mix until the chicken is evenly coated, then cover and let it marinate in the refrigerator for at least 30 minutes or up to 3 hours.
Preheat your air fryer to 375°F. While it heats, remove the marinated chicken from the refrigerator. Add cornstarch to a shallow bowl, then individually dredge each piece of chicken in the cornstarch until fully coated.
Lightly spray the air fryer basket with cooking spray to prevent sticking. Arrange the chicken in a single layer, leaving space between pieces. Spray the tops of the chicken with a little more cooking spray to help them crisp up. Air fry for 14 minutes, flipping halfway through, until golden and crispy.
While the chicken cooks, prepare the sauce. In a mixing bowl, whisk together gochujang, honey, coconut aminos, rice vinegar, and water until smooth.
In a large skillet, heat a drizzle of avocado oil over medium-low heat. Add the grated garlic and ginger and sauté for 1–2 minutes until fragrant. Pour in the gochujang mixture and bring it to a gentle simmer. Stir in the cornstarch slurry and continue to cook, stirring often, until the sauce thickens to your desired consistency.
Once the chicken is done cooking in the air fryer, transfer it to the skillet with the gochujang sauce. Toss well to ensure every piece is fully coated in the sticky, flavorful glaze. Serve the spicy Korean chicken over a bowl of steamed rice and top with your favorite veggies for a balanced, flavor-packed meal. Enjoy!