Bring the chicken broth, grated ginger and soy sauce to a boil. Taste, and season with sea salt and white pepper, to taste. In a small cup, make a slurry by combining the cornstarch and a little bit of chicken stock. Stir until dissolved. Slowly pour in the cornstarch mixture while stirring the broth, until thickened. Reduce heat to a simmer. Pour in the eggs slowly while stirring the soup in the same direction. The egg will spread and feather. Turn off the heat and add the green onion. Taste the soup and re-season with sea salt and white pepper, if needed. Serve immediately. Enjoy.