Reddit mentions of Japan: The Cookbook

Nancy Singleton Hachisu has written a few books that sound up your alley (e.g. Japan: The Cookbook). She's originally from the US but has lived in the Japan countryside for many years after marrying a Japanese man, and her writing reflects her extensive learning experiences and research.

I have these three that I like quite a bit:

Japan: The Cookbook

Preserving the Japanese Way

The Gaijin Cookbook

I personally love this cookbook for Japanese cooking. It's more of an archive of recipes than a how-to to Japanese cooking, but it does detail certain ingredients and techniques. This cookbook, however, does not shy away from hard to find ingredients; I can't even find all the ingredients I'm looking for some times, and there are Japanese groceries all around my area. Sometimes you just need to figure out whatever the alternate names for things are. Ironically, I was able to find Komatsuna under the Gai Choy, which I believe is the chinese word for the same thing (mustard greens). Same with Shungiku under Tung Ho (chrysanthemum greens).

The most important things I learned in this book was that the mirin I usually buy is actually not true mirin. Real mirin is made in a similar process to sake, while aji mirin (what most people are familiar with) is mainly corn syrup. Another thing I learned was that high quality rice vinegar is usually brown, not clear (like the kind I buy). Not to mention, homemade dashi (using bonito flakes and konbu) is significantly better than making it from hondashi (the dashi equivalent of boullion powder). Almost every recipe will use a combination of these things (with soy sauce of course), but it's also exciting trying out recipes with ingredients less familiar with the uninitiated (ume/sour plum, dried shrimp, kabocha/Japanese pumpkin, etc.).