Make the pastry by sifting the flour and salt into a warm bowl. Make a well in the centre of the flour. Heat the water over medium heat and add the lard. Melt the lard in the water and, when it is bubbling, add to the flour and mix thoroughly. Take a small amount and form into a ball. Keep the rest warm while making each pastry case. Divide 3/4 of the pastry into 8 even amounts for each pie and shape the crust round the base of a glass or jar approximately 7.5 to 8.5cm (3 to 3.5 in) in diameter. Make sure there are no cracks in the pastry. You can trim round the top of the case to make it even. As the pastry cools, remove the glass and continue until you have about a quarter of the pastry left to make the lids.
Fill the cases with the meat and add the gravy to make the meat moist. Roll the remaining pastry and use the glass to cut the lids. Wet the edges of the lids, place over the meat and press down lightly over the filling. Pinch the edges and trim. Cut a small hole or vent in the centre of the lid to allow the steam to escape.
Preheat the oven to 140 C / Gas 1.
Glaze tops with milk and bake for about 45 minutes. If the pies are not eaten immediately, they can be stored in the fridge but always ensure they are properly reheated before being eaten.