Ohitashi (boiled greens) (おひたし)
Ohitashi (also called hitashi or hitashimono) is a kind of cookery. This cookery name is derived from the process to soak ingredients in soup stock, but this process is often skipped, and simply boiled foods with soy sauce on it is also called ohitashi.
In ancient times, ohitashi was written as "浸物" (hitashimono). It is estimated that this cookery existed based on documents in the Nara period and the word "Hitashimono" also appeared in the records in 1517 in the Sengoku period (period of warring states in Japan). In the Edo period, there were some hitashimono recipes that used boiled-down sake or vinegar as a seasoning or those used marine products as ingredients including awabi (abalone), sea cucumber, or jellyfish, but after the Meiji period, vegetable ohitashi seasoned with soy source has become the main stream recipe for ohitashi.
How to cook ohitashi
Soak aona (greens), sansai (plants growing wilds in field and mountains), or mushrooms in soup stock after boiling them, and drain off water and seasoned with soy source just before serving. This is for adjusting the amount of seasoning according to individual taste. It requires careful attention since the excess of boiling cause them to lose flavor and food texture. Recently, ohitashi is sometimes cooked using microwave, but when using microwave, it has some bitter aftertaste due to the remaining scum (oxalic acid).
Typical ingredients are spinach, brassica rapa (a kind of Chinese cabbage), napa cabbage, rape blossom, or garland chrysanthemum. As well as dried bonito flakes and sesame seeds, Dashi-shoyu (soy sauce broth) is also used as a flavoring in ohitashi.
Agebitashi (deep-fried vegetables in soy and mirin broth)
Vegetables such as eggplants which are not boiled but deep fried and soaked in seasoned soup stock after removing oil by pouring boiling water are also a kind of ohitashi and in this case, it is particularly called "agebitashi."