1.making the soup stock In a big cooking pot, add 1L water, chicken, green parts of a leek and ginger. Heat over high heat and bring it to a boil. Once it boils, reduce the heat to low and simmer for about 10 min.
2. Remove from the heat. Take chicken, leek and ginger out to a plate. Strain the stock with a sieve to another big cooking pot. Add 1L water more into the stock, then set aside.
3. In a frying-pan, heat 1 tbsp oil and place the boiled chicken skin side down. Cook for about 3~4 min both sides or until a nice golden brown. Season with salt and pepper. Cut into slices and set aside.
4.making the soy sauce soup base In a small heat-resistant bowl, add the chopped leek (about 10cm) and garlic (grated). Set aside.
5. In a small cooking pot, add soy sauce, cooking sake, oil, sesame oil, balsamic vinegar, hondashi powder and sugar. Heat over medium heat until almost boiled. Remove from the heat and pour the soy sauce mixture over the leek in a bowl.
6. Add torigara powder and oyster sauce, mix well and set aside.
7. Cook noodles according to the package instructions. Meanwhile, place some shoyu soup base in a serving bowl and pour the soup stock (boiled). Immediately place the cooked noodle into the soup stock. Topping with chicken and leek (julienne) over the noodle. Serve hot!
You can change the quantity of shoyu soup base you add depending on how you like it.