Half-fill a saucepan with cold water and bring to the boil. Carefully add the quails’ eggs to the boiling water and boil for 2½ minutes. Drain the eggs through a sieve and rinse under running water until completely cold. Leave until the filling is made.
Squeeze the sausages out of their skins and into a large mixing bowl. Add the bacon pieces, pork mince, ginger and mace. Season with plenty of freshly ground black pepper. Mix with your hands until very well combined. Divide the mixture into two portions. Gently peel the shells from the eggs, taking care to keep the eggs as whole as possible. Put in a bowl and toss lightly with the flour until lightly coated. This will stop them being too slippery when they are put in the filling.
Preheat the oven to 200C/180C (fan)/Gas 6. Line a large, flat metal baking tray with baking parchment. If you don’t have a completely flat tray, turn your baking tray over.
For the pastry, put the flour and pepper in a food processor with the butter and 25g/1oz of the lard. Use the pulse setting to blend until the mixture resembles coarse breadcrumbs.
Put the remaining lard, four tablespoons cold water and salt in a small saucepan. Bring to a simmer, then add to the flour mixture with the motor running and blend until the dough comes together. Turn out onto a floured surface and knead lightly to make a smooth, pliable dough
Dust the baking parchment-lined tin with flour. Form the dough into rectangular block, and place on the baking tray. Dust a rolling pin with flour and roll out the pastry until it is around 6mm thick and makes a rectangle of 30 x 28cm/12 x 11in. You’ll need to turn the pastry a few times to roll it to the right size, working fairly quickly, before the pastry has a chance to stiffen.
Place half of the pork mixture lengthways down the middle of the pastry, leaving a 1.5cm/¾in boarder at each end. The pork should be roughly 25cm/10in long and 10cm/4in wide. Top with the floured eggs, standing on their ends and running next to each other all the way down the length of the pastry. Cover with the remaining pork mixture, making sure that all the eggs are completely enclosed, and press down lightly.
Brush one of the long pastry edges lightly with beaten egg and bring both sides to in the middle to encase the filling. (You may need to use the baking parchment to help you lift the pasty.) Press the all edges very firmly together to seal and trim the top neatly with a sharp set of kitchen scissors, leaving 1cm/½in or so for the crest. Crimp the top edge into a wiggly line on top of the pie.
Brush the pastry parcel evenly with beaten egg and bake for 15 minutes. Take out of the oven and brush with more beaten egg. The beaten egg will also help mend any cracks, if you have any. Return to the oven for a further 15 minutes or until the pie is golden-brown and the pastry and filling are completely cooked. Leave to cool.