Here I am using several authentic ingredients which may be hard to find outside of metro areas. Burdock root looks like a long parsnip but darker. It is known as gobo in Japan. The taste is distinctive and can be found in many Japanese cooking. When using burdock roots or gobo, it is best to soak in water after slicing or cutting with a bit of vinegar to keep from turning dark. For substitution, I would use carrot. Konnyaku is made from konjac potato and is found in the refrigerated section of a Japanese or Asian market in a similar package as tofu. It is normally whitish or brownish color and almost zero calorie and full of fiber. Its texture is jelly like but more firm and needs to be quickly blanched in hot water for about 2 minutes before using. If you cannot find it, just skip it since there is no substitution. Although konnyaku does have flavor its own, it is most often used for texture more than flavor. Mitsuba is an herb often used in soup dishes in Japan. It is sometimes translated as trefoil and looks similar to parsley but the taste is totally different. If you cannot find this, use some baby spinach. Other possibilites to add are anything seasonal vegetables such as asparagus, green beans, etc. That's what makes sukiyaki like this your unique dish. It can contain many things you prefer. Keep all ingredients separate ie in one place when cooking without mixing them all up like stir fry. Although traditional sukiyaki using the very best thinly sliced beef is wonderful, I really enjoy this method as well and it is more economical. The use of gobo and ramen comes Harris Salat, but it's not in his Hotpot cookbook.