"What are the Italian cooks doing behind the big old building?"
Translation:Mit csinálnak az olasz szakácsok a régi nagy épület mögött?
When there are two consecutive adjectives in English, should the order always be reversed in Hungarian? My answer was "Mit csinálnak az olasz szakácsok a nagy régi épület mögött?" but in the correct answer it becomes "régi nagy épület".
No, ordinarily there doesn't need to be any such reversal and there isn't any grammatical meaning to it. It's just a quirk. Probably the Hungarian sentence was translated into English and the translator correctly realized that "the old big building" sounds wrong (for no logical reason, just any arbitrary convention about the way those two particular adjectives are usually ordered).