All the flavours of Christmas dinner encased in hot-water crust pastry, and with a jewel-like topping of cranberry sauce. Serve chilled.
Make the pastry. Sift both flours and the salt into a large heatproof bowl. Rub in the butter until the mixture resembles fine crumbs. Make a well in the centre.
Melt the lard and goose fat with 200ml of water in a medium pan over a medium heat, until very hot but not quite boiling. Pour into the well, stirring continuously to form a dough.
Turn the dough out onto a lightly floured worktop and knead until very smooth and pliable.
Cut off 150g of the dough, wrap it in cling film and set aside to make the decorations. Roll out the remaining dough to a 25cm-diameter disc.
Set the disc over the cling-film-covered cake-tin base and mould it evenly over the base and down the sides of the tin to at least 7cm high. Chill for about 1 hour.
Make the filling. Melt the goose fat in a small pan over a low heat. Stir in the onion, garlic and salt and cook until the onion is very soft, then pour in the brandy. Stir well, boil for a few seconds, then tip into a large heatproof bowl. Leave to cool.
Add the clementine zest, mixed spice, mace, pepper and breadcrumbs and mix well. Add the remaining ingredients and mix again to combine.
Take 1 teaspoon of the mixture, shape it into a thick disc. Dry fry over a medium heat for a couple of minutes on each side until thoroughly cooked. Taste for seasoning and add more salt, pepper or spices to the rest of the uncooked mixture as needed. Cover the mixture and chill.
To assemble the pie, set the pastry case upright on the lined baking tray, ease out the tin and peel away the cling film. Fold the lined foil in three to make a long strip about 10cm high (paper side out). Wrap it around the outside of the pie case to make a collar, then tie it in place with string around the base, middle and top of the case. Brush the pastry base and sides with beaten egg (patch up any tears). Chill for 10 minutes.
Spoon half the filling into the pastry case and gently press down to form an even layer. Bang the tin on the worktop to settle the filling. Cover with a layer of chestnuts, then the sprouts, then half the pancetta strips. Top with the remaining filling and finish with the remaining strips of pancetta.
Trim off the excess pastry so that it’s slightly higher than the filling, then mould and curve the pastry over your finger to form a small lip.
Roll out the reserved pastry to 3mm thick and stamp out holly leaves. Brush the pastry lip with beaten egg, then attach leaves all around to form a wreath. Brush with more egg.
Place the paper-lined foil disc loosely on top, foil side up (don’t cover the wreath). Chill for 20 minutes. Meanwhile, heat the oven to 180°C/160°C fan/350°F/Gas 4.
Bake the pie for 30 minutes, then reduce the temperature to 150°C/130°C fan/300°F/Gas 2 and bake for a further 1 hour. Remove the pie from the oven.
Remove the collar and brush the sides and wreath with beaten egg and return to the oven for a further 25–30 minutes, until golden brown. The filling is cooked when a cooking thermometer inserted into the centre reads 75°C/167°F; or a metal skewer inserted for 10 seconds, then removed, feels very hot to touch.
Set the pie, still on the baking tray and with the foil disc on top, on a wire rack to cool. Then chill for at least 2 hours, preferably overnight.
Meanwhile, make the cranberry topping. Put the cranberries (no need to thaw if frozen), orange juice and zest, sugar, cinnamon, nutmeg and seasoning into a medium pan on a low heat. Cook, stirring frequently, until the berries burst and the sugar dissolves.
Increase the heat and boil for about 5 minutes, stirring, until very thick and sticky. Transfer to a heatproof bowl, leave to cool, then cover and set aside.
To serve, remove the foil disc and spoon the cranberry mixture over in an even layer.