Whisk together chicken stock (chilled or room-temperature), cornstarch, ginger and garlic powder in a medium saucepan until combined and no lumps remain.

Heat over high heat until boiling, stirring occasionally.

Meanwhile, whisk together the eggs and egg whites in a small measuring cup or bowl.

Once the broth reaches a boil, remove from heat. Then use a fork or whisk to stir the broth in a circular motion, while slowly pour the whisked eggs into the soup to create egg ribbons.

Stir in the sesame oil, green onions (optional) until combined.

Season with salt and pepper to taste. Serve immediately, topped with additional green onions for garnish.