Row of cakes? (3,5)
(Other definitions for bun fight that I've seen before include "Tea party (slang)" , "12 down party on an important occasion (slang)" , "Grand official party" , "Tea party - petty argument" , "Heated but petty argument" .)
(Other definitions for bunfight that I've seen before include "Tea party (slang)" , "Grand tea party - huge argument" .)