A good question. Purists claim that the true pasty crust is a white flour pie or “short” crust. And indeed if you look back forty or fifty years, the simple short crust is the most common. But why stop there? Travel back in time another few decades and you’d discover that a white flour-based short crust was an expensive luxury item. Then, many pasty crusts were made of a paste of dark, coarse-ground barley, which grew (and still does grow) well in Cornish soil. This made for a rather hard and gritty casing, but then if that’s what you’ve got, that’s what’s for lunch (it was the way of the world until extremely recently). When industrial farming and milling techniques made fine wheat flours cheaper and more common in the English West Country, did they switch? You bet, and in a heartbeat. Today you’d be hard pressed to find a barley crust in most places in Cornwall. Short crusts are considered the most authentic. Quite a lot of pasties are made with puff pastry these days, and mighty fine things they are too. However since it takes a lot of work and finesse to make a laminated dough, puff crusts were and are considered fussy and snobby by the standards of most Cornish housewives. That is, if there is such a thing as housewife anywhere in the world anymore.