I am American living in Ukraine, and I am not sure about how to change the keyboard to Russian on this Mac, so pardon an answer that is all in English.

I just prepared dinner, with mashed potatoes with butter and sour cream. It is a normal staple in America.

If you go to the supermarket here. there will be several kinds of sour cream, all commercial. If you go to the bazaar, there will be several dairy booths, and many different thicknesses and taste of sour cream. And cirok. Sour cream is common in America, cirok does not exist in America.