Pour chicken stock into a medium soup pot and bring to a boil.

Stir in sesame oil, salt, sugar, white pepper, and MSG (if using). Add in turmeric. Taste and adjust seasoning if desired. 

Mix together cornstarch and water in a small bowl, mixing well. Add mixture to the pot, stirring continuously as you pour slowly. If your soup is too thin, you can add more cornstarch. 

Using a ladle, stir the soup in a circular motion as you slowly add the beaten egg. 

Ladle the soup into bowls and top with scallions before serving.