PIETRO Dressing Japanese Style Soy Sauce (280ml) 'Pietro dressing original' is a dressing of spaghetti shop Pietro, which opened in 1980, Fukuoka Tenjin. Pietro dressing became a reputable dressing and is created by taking advantage of the unique technology used to make it. It is an onion and soy sauce flavour. Avoid placing in direct sunlight and store at room temperature. After opening, store in refrigerator. Shake well before using.