In a wok or saucepan, bring the chicken broth to a simmer. Add the soy sauce and bring to a boil. Whisk in cornstarch.
Once the cornstarch is dissolved, bring the soup back to a boil. Very slowly pour in the eggs in a steady stream. To make shreds, stir the egg rapidly in a clockwise direction for one minute. To make thin streams or ribbons, gently stir the eggs in a clockwise direction until they form.