Pork wonton soup

Name: Pork wonton soup
Cook time: 30 min
Total time: 30 min
Cuisine: Chinese
Ingredients: 2 litres (8 cups) chicken stock; 3 spring onions, green part coarsely chopped, white part finely chopped (reserve for wontons); 1 tbsp soy sauce; 1 tsp sesame oil; 1½ cups shredded Chinese cabbage; 1 tbsp julienned ginger; 500 gm minced pork; 2 tsp finely grated ginger; 1 garlic clove, finely chopped; ¼ cup coarsely chopped coriander, plus extra to serve; 24 wonton wrappers; 1 eggwhite, lightly beaten