2. In a bowl, beat in one egg. Stir in 1/2 tsp salt and 1/2 tsp black pepper.
3. Marinate chicken in egg mixture for around 10 mins.
4. In another bowl, add in 1/2 cup flour and 1/8 cup corn starch. Mix well.
5. Heat a skillet and pour in enough oil. Dip chicken in the flour mixture and deep fry them till slightly golden brown or the outside flour shell becomes hard.
7. Add in 1 tsp cooking wine, 1 1/2 tsp soy sauce, 5 tsp vinegar, 1 1/2 tsp water, 3 tsp sugar and 2 tsp orange zest. Stir well.
8. Add fried chicken into the sauce. Keep stir fry to let the chicken be coated with sauce evenly.
9. When the sauce is almost dry, add in a little starch water. Sprinkle some chopped spring onion. Quicker stir evenly and serve.