Mix the filling ingredients together and leave for a few hours for the flavour to develop, or overnight preferably.
To make the pastry, mix the flours and salt together in a bowl. Heat the water lard in a small saucepan until the lard has melted, bring the water to a simmer then pour the water into the flour. Mix the flour and water together with a wooden spoon being careful as the mixture is very hot. When the pastry is combined turn the dough out onto the surface and knead well for a couple of minutes. Place the pastry back into the bowl, ready to use.
To make the pork pies, mix together all the ingredients, then divide the filling mix into 4 and then divide the pastry into 4. Line a tray with greaseproof paper and rub a little lard over the paper. Remove ¼ of the pastry from 1 piece of dough and set aside. Flatten the rest of the pastry in your hand to form a rough disc. Place 1 lot of the filling mix on the pastry and fold the edges of pastry around the filling. Place the pie onto the tray and then brush with a little of the egg around the edges. Flatten the ¼ piece of pastry you removed earlier to the same size as the top of the pie and place on top. Crimp the edges together, making a flat top and then brush the pie with egg. Make a hole in the centre to release steam. Repeat with the 3 remaining pieces of dough and pastry.
Place the pies in a preheated oven at 200c for 20 minutes and then turn the oven down to 180c for another 20 minutes or so. The pies are cooked when the pastry is golden and the centre of the pie, (when temperature probed) reaches 75c. Remove the pies and allow to cool on a rack.
Mix the gelatine sheets into the warm chicken stock and taste for seasoning, adjust with salt and pepper as necessary.
Once cooled, use a small funnel to carefully pour the liquid jelly into the pies. Return to the fridge for 1 hour to set. Serve the pies with our piccalilli and a wedge of cheddar for a seriously delicious meal.