Okay, there's a little more to it than that, but not much. Hot water pastry is simple, perhaps because it seems to break all the rules held most dear to the experienced pastry chef. Keeping it cool, refraining from overworking the mixture - all of that means nothing when it comes to hot water pastry. Something of a masochist, this pastry likes it hot and will thank you kindly for a good beating...
350g (12 oz) plain flour
A pinch of salt
1 egg yolk
4 tablespoons of milk
4 tablespoons of water
25g (1 oz) butter
75g (3 oz) lard
Begin by sifting the flour and salt into a bowl and making a well in the centre. Mix the egg yolk with one tablespoon of the milk and pour it into the well. Don't worry about it needing to be cold; warm milk and flour is perfectly acceptable for hot water pastry, mainly because in a moment you're going to heat the lard, butter and remaining milk and water in a saucepan.
Only heat it gently at first, just to allow the lard to melt, and then bring it to a brisk boil. Pour this into the well and mix until everything is completely blended. By this time your mixture should have cooled to the point where you can comfortably handle it, in which case it's time to tip it onto a floured work surface.
Knead it thoroughly until the pastry is smooth, at which point the pastry needs to rest for about half an hour. Keep it warm as it rests - the best way being to place in a bowl over a saucepan of hot water. Covering it with a clean cloth at this point is also beneficial.
Following this the pastry can be rolled out to a thickness of about 5 mm (quarter of an inch) and used as required. To create a pie case the pastry can be moulded around the bottom of a jar. Upon removing the jar it can be filled with whatever takes your fancy - rich pork and onion filling or a beef and gravy mixture - and topped off with a pastry lid before baking. Delicious!
Hot Water Pastry: Merely one of a series of adventures in the peculiar realms of British cuisine!