apple pie
as American as apple pie: seeamerican.
in apple-pie order in perfect order or neatness.
☞ The origin of the phrase, which is first recorded in 1780, is unclear. It may be traceable back to Old French cap a pie 'head to foot'; it may be an alteration of French nappe pliée 'folded cloth' (which is where 'apple-pie bed' comes from); or it may simply be a reference to a literal apple pie.