Soup of Salted Duck Eggs, Sliced Pork and Mustard Greens

Name: Soup of Salted Duck Eggs, Sliced Pork and Mustard Greens (Jie Cai Xian Dan Rou Pian Tang 芥菜鹹蛋肉片湯)
Cuisine: Chinese
Ingredients: 1½ tsp potato flour; 2 salted duck eggs; 300 g preserved mustard greens; 20 g piece of ginger; 1.5 litres stock; 3 tbsp cooking oil; Salt; ½ tsp salt; ½ tbsp Shaoxing wine; 150 g pork tenderloin