The full proverb is indeed the proof of the pudding is in the...

The full proverb is indeed the proof of the pudding is in the eating and proof has the sense of ?test? (as it also has, or used to have, in phrases such as proving-ground and printer?s proof). The proverb literally says that you won?t know whether food has been cooked properly until you try it. Or, putting it figuratively, don?t assume that something is in order or believe what you are told, but judge the matter by testing it; it?s much the same philosophy as in seeing is believing and actions speak louder than words.