Buttery pastry dough:
2 1/2 cups plain flour
3 tsp sugar
1/2 tsp fine sea salt or table salt
250 g cold unsalted butter, cut into 1 cm cubes
1/3 cup ice water
1/4 cup extra-virgin olive oil
1 small brown onion, finely chopped
1 celery stalk, finely chopped
1 small carrot, finely chopped
60 g prosciutto di Parma (about 5 slices), finely chopped
875 g beef mince
Sea salt and freshly ground black pepper
90 g chicken livers (about 3), rinsed, cleaned, and finely chopped
1 1/2 Tbsp tomato paste
1/8 tsp ground allspice
1/2 cup dry white wine
1/2 cup milk
1 1/2 Tbsp plain flour
3 cups salt reduced beef stock
To assemble pies:
Plain flour, for dusting
Buttery pastry dough, shaped into 12 discs and chilled (recipe below)
1 large egg
1 Tbsp cream
Buttery pastry dough method:
In a food processor, combine the flour, sugar and salt. Pulse to blend. Add the butter and pulse about 10 times, or until the butter is in pea-size pieces; do not over-process. While pulsing the processor, add 1/3 cup of the ice water, then pulse until just moist clumps of dough form, adding more water 1 tablespoon at a time if necessary.
Transfer the dough to a work surface and divide it in half. Divide each piece of dough into 6 pieces and shape into discs. Wrap individually in plastic wrap and refrigerate for at least 30 minutes before rolling out.
Meat pie filling:
To make the filling, heat a large heavy pot over medium-high heat. Add the oil, then add the onion, celery and carrot and sauté for about 5 minutes, or until the vegetables are tender but not browned. Add the prosciutto and sauté for 2 minutes.
Crumble the beef into the pot and season with salt and pepper. Cook, stirring with a wooden spoon to break up the beef, for about 5 minutes, or until the meat is just cooked and no longer pink. Add the chicken livers and cook for about 2 minutes, or until the livers are just cooked and no longer pink. Add the tomato paste and allspice and cook, stirring, for about 2 minutes, or until the tomato paste is well blended.
Stir in the wine and cook for about 2 minutes, or until it evaporates completely. Reduce the heat to medium, add the milk and cook, stirring occasionally, for about 2 minutes, or until the milk has reduced by three-quarters and the sauce is thick and creamy. Sprinkle the flour over the mixture and cook for about 1 minute, stirring constantly, or until well blended.
Add the stock, bring to a simmer, and simmer for 25 minutes, or until the liquid has thickened and reduced by one-quarter. Season with salt and pepper. Set the mixture aside to cool. (You should have about 4 1/2 cups filling.)
To assemble and bake the pies, position a rack on the lowest rung of the oven and set a baking tray on the rack. Preheat the oven to 200°C. (Being close to the source of heat will help the bottom crusts bake and brown properly.)
On a floured work surface, roll out 1 disc of dough to a 15 cm round about 2.5 mm thick. Line a 12 cm disposable aluminium pie pan with the dough. Repeat with 5 more dough balls and pie pans. Divide the filling among the pans, using about 3/4 cup filling per pie.
Roll out the remaining 6 dough pieces to 15 cm rounds and lay them over the filling. Trim the dough overhang to 1 cm. Pinch the bottom and top crusts together to seal, and fold them under. Crimp the edges. Using your finger, make a hole in the centre of each top crust.
In a small bowl, whisk the egg and cream to blend. Using a pastry brush, lightly brush the tops of the pies with the egg-cream mixture.
Place the pies on the preheated baking tray in the oven and bake for about 40 minutes, or until the crust is deep golden and the filling is bubbling. If the crust begins to brown before the filling bubbles, tent the pies with foil. Let the pies cool on a wire rack until warm before serving.