Reserve a quarter cup of the chicken stock and set to the side.
Add the remaining stock to a small pot, and bring to a simmer. Season with a pinch or two of salt, the same with the cracked black pepper. Stir, then add in the soy sauce and sesame oil.
Add the remaining chicken stock to a small bowl, then stir in the corn starch, and stir until it dissolves.
Pour the corn starch slurry into the stock, and give a good stir. This will thicken the stock a bit.
Slowly stir in the egg, and using a fork, stir in one direction. Continue stirring and let the eggs set.
When you are ready to serve, ladle in the egg drop soup into your serving bowl, and top with a generous amount of green onions.
The soup has velvety strands of egg, which are not very apparent in my picture (but trust me they are there), and the small amount of sesame and soy sauce balances this stock out just right. That along with the green onions make this a very comforting bowl of soup.