каша

The Proto-Slavic root kaša referred to any cooked grain: millet, rye, wheat, or the buckwheat that later became its most common form in Russia. The word appears in Old Church Slavonic manuscripts of the 10th century as a general term for boiled cereal. In Old Russian chronicles of the 12th century, kasha appears at feasts marking treaties and weddings.

By the medieval period, kasha had become so fundamental to Russian diet that the word entered common speech as a synonym for meal or food itself. A 15th-century proverb runs: shchi da kasha, pishcha nasha, meaning cabbage soup and porridge, that is our food. The Russian military depended on kasha as its primary field ration from the medieval period through World War II.

Buckwheat kasha, made from roasted buckwheat groats called grechka, became the dominant form in Russian cooking by the 17th century. Buckwheat is not wheat at all but Fagopyrum esculentum, a plant whose seeds resemble wheat grains. It reached Eastern Europe from Central Asia along trade routes by the 14th century, and Russian cooking adopted it so completely that grechnevaya kasha became synonymous with kasha itself.

Ashkenazi Jewish immigrants brought kasha to North America in the late 19th and early 20th centuries. In American Yiddish, kasha came to mean specifically buckwheat groats. Kasha varnishkes, buckwheat groats cooked with bow-tie pasta and onions, became a staple of Jewish-American deli cuisine, and the word entered English dictionaries by the 1890s.