You’ll find it in supermarkets and grocery stores as kasha.
In Russian, the word kasha (????) is quite a bit less specific. Kasha means any cooked grain. You could have oatmeal kasha, or cream-of-wheat kasha. Grits would be corn kasha, and cooked barley could also be kasha.
Ironically, buckwheat is not technically a grain, as it’s not a grass. It’s more closely related to beans than to wheat (I’ll leave the exact taxonomy to botanists, for us cooks the slight difference is merely amusing). In practice, it cooks pretty much the same way. And of course you can make buckwheat flour (but then you can make bean flour, and almond flour, and coconut flour… and none of them work like wheat flour… but then rye or barley flour don’t work like wheat flour either… but I digress).
So, buckwheat. I used to dislike it intensely as a child. Maybe it was because of the way Mom cooked it. Maybe it was because my childhood taste buds wouldn’t accept it. Whatever the reason — I wouldn’t eat it. And it was a big deal, because we rarely had alternatives to what was served for dinner. Not because of authoritarian rules, but because it simply wasn’t there.
Then one day I tasted buckwheat at a restaurant, and my world changed. Again, it may have been the different way it was prepared. Or my matured tastebuds. Or just the right time and place and mood and everything. But from then on I started really, really liking buckwheat.
It’s flavor isn’t mild and neutral, like cream-of-wheat or oatmeal. It’s more robust, almost nutty. It goes with every type of Russian meal and dish you could think of. As a side dish, as a filling in pastries or pasta, baked in casseroles, or simply as cereal, warmed up with a little hot milk and sweetened with sugar or honey.
And as some of my students discovered during their stay in Russia, it can get to be a little too much. Well, even the best desserts can become too much of a good thing.
Proper Russian buckwheat kasha is made with whole groats. What you find in American grocery stores may or may not be whole groats. It is also toasted (roasted) buckwheat, and again, you may find raw or toasted buckwheat. The preparation of buckwheat is about as complicated as the preparation of rice (hmm… I wonder… would it work in a rice maker? has anyone tried?). Some cooks like to toast buckwheat having first mixed it with a whole egg, to help keep it fluffy.
Leftover buckwheat kasha can easily be reheated, or used in one of many recipes with binders and fillers and baked in the oven: frittata-like, or in a dessert with fresh cheese. It can also be used as a filling for pirozhki (pronounce it [pee-rohzh-KEE], with a stress on the KEE), the small filled pastries similar to the Polish pierogies.
In other words, it’s a staple.
Still, if a Russian speaks of kasha, you have to wonder, what kind?