Cut the chicken into bite-sized pieces.
Slice the onion, sweet potato, carrot, and cabbage thinly.
Make the sauce by mixing the given soy sauce, gochujang, chili powder, minced garlic, cooking wine, and pepper.
Heat oil in a pan and stir-fry the chicken.
Add the sauce to the chicken and mix well.
Add the prepared vegetables and stir-fry together.
Continue stir-frying until all ingredients are cooked thoroughly.