Cornstarch

Katakuriko, originally made from the root of the dogtooth violet and now made from the considerably less exotic Irish potato, is a thickener for cooked sauces. Cornstarch is a good substitute. It is mixed with water in varying ratios, depending on the dish, and then added near the end of cooking. Always stir the mixture again briefly just before using and add it slowly, stirring it into the dish until the desired consistency is achieved. Cornstarch is also a good coating for meat or chicken for deep-frying (see Toriniku Kara-age), yielding crispy results.