In a large pot over medium-low heat, add in the sesame oil, grated garlic, and grated ginger. Saute this for about 15-30 seconds or until it smells fragrant.
Add the broth and the green onions to the pot and stir. Bring the heat up to medium-high and let it come up to a low boil.
Meanwhile, whisk all of your eggs. Do this really well, making sure the whites and yolks really get broken up and combined.
In a small bowl, whisk together the cornstarch and 3 tbsp of water.
Once the broth has reached a low boil, turn down the heat to simmer and with a large spoon, stir the soup creating a slight whirlpool. Keep stirring slowly and drizzle in the whisked eggs. The slower you pour, the thinner the egg ribbons will be. This may be easier for you to pour from a vessel that has a spout, such as a large measuring cup.
Stir the cornstarch mixture once more, as it tends to separate. Using the large spoon, stir the soup while adding the cornstarch mixture. Cook for just 30 seconds longer and then turn off the heat and it's done!