Wash the tofu several times under running water and set a side.
Combine water and salt and bring to a boil.
Drop the tofu into the boiling water and boil for five minutes. Drain and lightly press with your hand to remove excess water.
Combine tofu and eggs. Make sure the tofu cubes are covered with eggs.
Heat pan and add the cooking oil. Add the whole tofu and egg mixture. Flip when one side is already golden brown. Slice the tofu using the tip of a wooden spatula to separate. Toss until all sides of the tofu are golden brown. Set a side.
Using the same pan, add olive oil and ground chicken. Mix and toss until chicken is slightly golden brown. Bring chicken on the other side of the pan and sauté garlic, onion, spring onion stalks and shiitake mushrooms.
In a bowl, combine oyster sauce, soy sauce, sesame oil, water, doenjang, brown sugar and ground black pepper. Mix and pour into the pan. Boil and simmer the mixture for 10 minutes over low heat.
Premix water and cornstarch and pour little by little into the pan to thicken the meat mixture. Stir constantly. Add the tofu and toss to evenly coat the tofu cubes. Garnish with chopped onion spring.
