Precooked soy flour has the advantage of needing very little cooking. It can even be used to make soy milk directly, without cooking.
Soy also has some unique qualities. It is much higher in protein (typically about 80-100% higher than most beans). It is also richer in calories (due to higher oil content), and is considered a higher-quality protein (with a better distribution of essential amino acids).
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(Some of these precooked soy powders are much better than others, and there is a wide price range. Some go for about 1.19/lb (or less if bought in bulk quantities). Others are up to six or seven dollars a pound. Different ones seem to be processed differently. The simplest, purest ones I have seen are just soy flour that has been cooked and dried. Some of those are among the most reasonably priced.)
(One other thing about soy flours -- if they have the full oil content, they can spoil. They have to be eaten fairly soon, or refrigerated or frozen to last in storage long-term. (Short-term they are fine.))
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There are also soy nuts.
Raw soybeans can be pressure-cooked in a large batch, then drained and spread out on cookie sheets, and dried in a warm oven.
They can be very good this way, and are ready to eat.
Most people like them best with some kind of seasoning -- they are easy to season before spreading them out to dry, and there are many options and varieties of seasonings, including some good exotic ones.