Cut the chicken into bite-sized pieces and peel the sweet potato, then dice into small cubes.
Season the chicken with salt and pepper, then coat evenly with starch.
Pour a generous amount of cooking oil into a pan and fry the chicken and sweet potato until crispy.
Place the fried chicken and sweet potato on a paper towel to drain excess oil.
In a pan, combine soy sauce, sugar, gochujang, cooking wine, and minced garlic to make the sauce.
Add the fried chicken and sweet potato to the sauce and toss thoroughly.
Neatly pack rice, sweet & spicy chicken, sweet potatoes, salad, and other ingredients into a lunchbox container.