
Dice the chicken thighs into 1-inch pieces and set aside.
In a bowl, whisk together the egg, flour, cornstarch, salt, pepper, garlic powder, and ginger powder to form a batter.
Coat the chicken pieces in the batter, ensuring they are fully covered.
Heat vegetable oil in a frying pan over medium-high heat. Fry the chicken pieces until golden brown and crispy, then remove and drain on paper towels.
In a separate pan, combine ketchup, soy sauce, sesame oil, gochujang, rice vinegar, brown sugar, and butter. Heat until the sauce is smooth and slightly thickened.
Toss the fried chicken pieces in the sauce until they are well coated.
Serve the Korean Popcorn Chicken hot, garnished with sesame seeds or green onions if desired.
