1. Ingredients: 300 grams of yam, 180 grams of chicken breast, 30 grams of green beans, half a green onion, two cloves of garlic, a small piece of ginger, a spoonful of egg white, a spoonful of cooking wine, salt (cured meat) 1/3 tsp, half a tsp of sugar, two tsp of starch, half a tsp of white pepper, half a tsp of oil, one tsp of salt (for frying), grind black pepper five times, half a tsp of white vinegar (rice vinegar) .

2. Wash the chicken breast, remove the fascia, cut into small pieces, and start marinating: one spoon of egg white, one spoon of cooking wine, two small spoons of starch, 1/3 small spoon of salt, and half a small spoon of sugar.

3. Mix half a teaspoon of white pepper and a spoonful of cold water in one direction with chopsticks until the chicken absorbs the water and marinate for half an hour.

4. Peel the yam, cut it into pieces the size of diced chicken, and soak them in a basin with half a spoonful of rice vinegar for about fifteen minutes.

5. Boil water in a pot, blanch the green beans for one minute and set aside. Then add the yams and blanch them for two minutes, remove and drain into cold water and set aside.

6. The onions, ginger, and garlic have been chopped, the chicken has been marinated, and the yams and green beans have been blanched.

7. Add oil to the wok, stir-fry the onions, ginger and garlic, add the diced chicken and stir-fry quickly.

8. As soon as the chicken changes color, add yams and green beans, add a small spoonful of salt and a spoonful of oyster sauce and stir-fry evenly.

9. Grind black pepper a few times according to your preference and stir well.