These potato croquettes, originally of European origin, have been enthusiastically adopted by the Japanese, and are readily found in shops and restaurants in Tokyo. Serve with a drizzle of Tonkatsu sauce, on a bed of shredded cabbage. For ease of preparation, assemble all the ingredients before beginning. You can make your own Tonkatsu sauce (a recipe follows, which can be doubled if you wish) or buy some commercially made. The Bull-Dog brand" (burudoku tonkatsu soosu) is popular in Japan. Preparation time does not include chilling time.