Fill a pot with water and boil the chicken breast until cooked through. While the chicken is cooking, prepare the other ingredients: dice the carrot into small cubes, rinse the sweet corn, finely chop the shiitake mushrooms, and mince the cilantro.

Add the sweet corn, carrot, and mushrooms to the chicken broth. Season with MSG, fish sauce, and salt to taste. Cook until the carrot and corn are just tender, then add the shredded chicken from step 2 and continue to cook until the soup comes to a boil. For a clearer soup, skim off any foam that rises to the surface while cooking.

Dissolve 5 teaspoons of cornstarch in half a small bowl of cooled, boiled water (cornstarch doesn't dissolve well in hot water, so use cool water). The amount of cornstarch depends on how thick you want your soup; here, 5 teaspoons are used for about 8 cups (2 liters) of water. Once dissolved, slowly pour the cornstarch mixture into the simmering soup, stirring until the soup thickens and gently bubbles.

Add 1 teaspoon of ground black pepper and stir well. If you like it spicier, add more pepper or a little Korean chili powder. Don't forget to add the cilantro.

Finally, add the egg. You can use the whole egg or just the yolk, but my family prefers the whole egg, so I crack it directly into the pot. After adding the egg, stir the soup in one direction to create beautiful egg ribbons.

Turn off the heat and ladle the soup into bowls. Enjoy!