Fu, the mother of seitan
Vegetarians are probably familiar with seitan as a meat substitute. Seitan is wheat gluten that has been kneaded in such a way that the gluten threads align themselves to resemble meat. It was invented by advocates of the macrobiotic food movement in Japan, specifically as a meat substitute, in the 1960s. (Fairly accurate (from what I've read elsewhere) Wikipedia entry.)
But way before there was a macrobiotic movement, let alone seitan, people in Japan were already eating a wheat protein product called fu (麩). Like seitan, fu is made from the gluten that is extracted from wheat flour. Sometimes the gluten is mixed with other ingredients. There are two kinds of fu: raw (namafu 生麩), which is basically fresh fu; and grilled and dried (yakifu or yakibu 焼き麩). Here I'd like to focus on the dried kind which is much easier to get a hold of for people outside of Japan. It's also a great pantry item, since it keeps for a long time.
How yakifu is made and types of yakifu
Yakifu is traditionally made by forming raw fu into various shapes, then slowly grilling it over a flame until barely colored on the outside and totally dried out. It has various names according to how it's made, and where it comes from. Here are three types of yakifu that I happened to have in my pantry:
From top left going clockwise, they are called komachibu, chikuwabu, and shounaifu. (Chikuwabu is called that because it resembles chikuwa, the fish paste product that's popular in oden.)
Here's a closeup of the komachibu, which is the kind that I find to be most versatile.
As you can see, it looks like little dried bread slices. That's because essentially that's what they are, except without the yeast and such.
Another kind of dried fu is kurumabu, wheel-shaped fu that are about the size of a doughnut. They are often used as meatless 'steaks' and such. I can't find kurumabu at my local Japanese grocery store, but you may be able to at yours.
Here is a map of Japan showing different kinds of fu and where they come from (Japanese).
A meatless protein
100 grams of dried fu has 369 calories, almost no fat and 28 grams of protein. So like seitan, it's a pretty good vegan protein. The only people for whom fu would not be suitable are those who are gluten intolerant. (Of course this applies to seitan as well.)
But what does it taste like?
On its own, dried fu is pretty tasteless. It's like a soft sponge that absorbs any flavors you can throw at it. The texture when dry is like stale bread, and when reconstituted it's soft and rather silky. If seitan has a texture a little like chicken, I'd say that fu, especially komachibu, is a bit like scallops.
How to use dried fu
The easiest way to use dried fu is to just throw some into a soup or stew. You may have already encountered them in miso soups. You don't have to limit it to miso soup though. Put some into a hearty vegetable soup, simmer briefly, and you have a fairly nutritionally complete meal. The komachibu and chikuwabu will taste like fluffy soft quenelles; the shounaibu is just a bit more dense in texture.
You can put them in in the last few minutes into a stew as well, meatless or not. If you simmer it for too long, it will start to disintegrate. (Shounaibu is more sturdy, since it's thinly stretched and folded.)
A slightly more advanced way is to reconsitute it first in plain water, then to stew it and so on. Fu is such a popular ingredient in sukiyaki that some people called dried fu sukiyakibu. Do remember though that the reconstituted sponge has no flavor, so you'll have to add it in by cooking it in a bit of soup or broth or sauce first.
Modern cookbooks have devised other ways of using dried fu; for example, Yumiko Kano, a cookbook author I've mentioned here several times before, uses komachibu as a base for mini-canapes. I haven't tried this myself yet but it's an intriguing idea.
As a first step though, try adding a few to a soup and see how it goes!
(And here's a panfried komachibu recipe over on Just Bento.)
Although fu is a very commonly available product, seitan is virtually unknown outside of macrobiotic circles in Japan. I actually didn't even know it had Japanese origins - I thought it came from somewhere in southeast Asia, like tempeh! It's ironic that seitan is much better known outside of Japan - maybe because it's used in things like Tofukey.