I have sadly neglected this site, and also the email and comments received. All I can say is bad on me. Anyway, I have received several emails about Japanese food, and I'd like to answer them here in the hopes that it can help more then one person at a time.
Q. How do I make tonkatsu sauce?
As I wrote in my tonkatsu (fried pork cutlet) article, I don't make my own tonkatsu sauce - I use "Bulldog" brand tonkatsu or chu-noh (medium-thick) sauce. There are other brands of these sauces too like Kagome. The fact of the matter is, most Japanese restaurants use commercial sauces too (hey, most burger places use prepared mustard and ketchup!), unless they specialize in tonkatsu. If you can't find Bulldog brand sauce at your local Japanese or Asian grocers and you are in North America, A1 steak sauce is a quite acceptable substitute, though it's rather more "tangy" than Bulldog brand. You can try toning A1 down a bit by adding some sugar, or mixing it with some ketchup. The base flavor of tonkatsu sauce is Worcestershire sauce plus various ingredients (onions, spices, fruit such as apple, etc.)
Q. How do I make that ginger salad dressing that is served in Japanese restaurants?
First of all, that ginger-salad dressing that vaguely resembles...well, let's not go there, but it doesn't look too appetizing does it? Despite its widespread use in many American Japanese restaurants, it is definitely not Japanese. I have not researched this in depth so I may be totally wrong, but I suspect that it was invented at Benihana. I hate the stuff, so I never touch it (if a side salad comes covered in it I leave the salad alone) so I can't really tell you how to make it.
That's not to say that Japanese people do not put dressing on their salads. Actually, Japanese dressing manufacturers have perfected the art of the low or non-oil salad dressing. Usually it's a tasty mixture of various herbs and spices such as shiso, ginger, sesame seeds, umeboshi (pickled plums), and such in a water base. Give them a try if you encounter them at an Asian or Japanese grocers. I'll try to post some homemade Japanese style non/low oil dressings soon.
Q. Are there any good online sources of Japanese food?
[Edited in 2007:] I can now recommend the following:
Q. Can I make miso soup in batches and freeze it, like I do with other soups?
Most European/American soups improve with age as it were, up to a point, but not all. For instance watercress soup can taste quite dreadful if you leave it for too long - it loses that fresh flavor. Miso soup is at its best when freshly made, because the delicate flavor of miso dissipates quite fast.
What you can do is to make the dashi stock in batches and freeze them. Keep in mind however that it only takes 15-20 minutes, minus the time it takes to soak the kombu seaweed for a while (you can just dump it in a pot a bit before) to make the dashi, and from there to miso soup is only the time you need to cook through whatever you put in. If you put in fresh sliced mushrooms, or tofu cubes, or tender greens, that's only a couple of minutes. So I've never found it worthwhile to freeze dashi myself.
Q. I've seen red and yellow (brown? white?) bean paste at an Asian grocery store, and I don't know which is the right one to use.
The best thing to do is to ask the store people which one is right for miso soup. If you are shopping at a general Asian grocery store, be sure the bean paste you are getting is Japanese miso, because other Asian cuisines also have their bean pastes - which taste quite different. Some commonly seen Japanese brands include Hanamaruki, Takeya and Maruman. Some U.S. companies (with Japanese names) also make miso, like Yamashirushi (I've only ever seen those in California though).
Q. Are ramen noodles a healthy snack?
I'm not sure why, but 3 people asked me this. The answer is, absolutely not! In Japan instant ramen noodles are regarded on the same level as potato chips or nachos in terms of bad-foodness. Most of the badness comes from the soup, which is high in sodium and often has quite a lot of fat too (some kinds even come with an extra pack of sesame oil, or, gasp, lard!) The noodles are made from highly refined white flour. In olden times, the noodles were deep fried to dehydrate them, though nowadays most brands are air-dried. Still, instant ramen is defintely Bad For You. (Of course, I love potato chips too.... :) )
I'm sure I've forgotten some other questions...if you have any please leave a comment and I'll try to respond in a more timely manner!