When I was in Yeshiva, it was often quoted that "some opinions" require Bishul Yisroel on any food item that has a form that is served "Al Shulchan Malachim". So, for example, potatoes would always require Bishul Yisroel even in the form of potato chips because some form of potatoes are prepared for state dinners and the like.
A while ago I was talking to a serious Talmid Chocham about some Kashrus issues, and that opinion came up and he started saying "That opinion ..." and caught himself. I assume he didn't want to denigrate it (this is my personal projection onto the conversation), but didn't hold by it. (His personal practice was to buy only Bishul Yisroel potato chips in a neighborhood where they are readily available and even cheaper than the other kinds, but when traveling he didn't worry about it).
Who's opinion is it that has that stringency of following the food item instead of the specific way it is being made?