The one thing you cannot do without when eating tofu is soy sauce. Just cutting tofu into handy slices and adding a dash of soy sauce will create a simple and tasty side dish. Soy sauce may well be the ideal partner for tofu.
Along with tofu, soy sauce came to be widely used among the common people of Japan from the mid Edo period (1603-1867) onwards.

A book called “Tofu Hyakuchin” (100 Tofu Delicacies)

The book “Tofu Hyakuchin”, which contained one hundred tofu recipes, was published in 1782 towards the end of the mid Edo period. Of the one hundred recipes, forty four require flavoring/seasoning with soy sauce. The next most commonly used flavoring/seasoning is miso, which is used in eighteen recipes.

Miso and soy sauce are both essential seasoning ingredients in Japanese cuisine, and both are derived from soybeans. However, in terms of compatibility with tofu, miso does not hold a chance against soy sauce in comparison.

Although a variety of ways of eating tofu are introduced in the “Tofu Hyakuchin”, in reality, it seems that the common people of the Edo period normally ate “hiya-yakko”, a simple dish of cold tofu with a little added soy sauce. In the same way, a winter favorite was “yu-dofu”, again a simple dish, boiled tofu with a dash of soy sauce.

Both these side dishes use the same soy sauce, but there was a difference; pure soy sauce was used for “hiya-yakko” while soy sauce mixed with bonito stock was used for “yu-dofu”. This difference in the use of soy sauce gives an idea of the food consciousness of the Edo people.

During the Edo period, thrift statutes were enacted on three occasions in order to save the Bushi caste from financial difficulties. These statutes focused on cotton and tofu. Attempts were made to revitalize the financial situation by switching to cotton attire and using tofu as a cheap source of nutrition. Along with its ideal partner, soy sauce, tofu was an essential food of the Edo period.