My mother (z"l) was pure Litvak and we grew up eating potato latkes with sour cream. If Litvaks were supposed to eat latkes with applesauce, she didn't know that
or used the sour cream only to please my father (z"l), who was pure Ukrainer. I doubt it that, though, because he was strictly a meat and potatoes man and I can't recall
him ever eating the latkes, even on Chanuka!
Oh yes, my mother, who spoke fluent Russian as well as Yiddish and English, always spoke of "borshch" rather than "borsht." Borshch is the
Russian pronunciation. My father understood Russian more than he spoke it, but he and my mother used Russian, when they spoke of things the kids were not
supposed to understand. We kids spoke English and Yiddish.