1. Preheat oven to 325°F (160°C).
2. Cut pork into several large chunks. In a large ovenproof pot with a tight-fitting lid, combine pork, 1 tsp (5 mL) salt, pepper, stock, wine, onion, bay leaves and thyme. Bring to a simmer over medium heat, cover and bake in preheated oven for 2½ to 3 hours or until meat shreds easily. Remove pork from braising liquid and set aside.
3. Remove and discard onion, bay leaves and thyme from braising liquid; skim as much fat as possible and reduce over medium-high heat to 1 cup (250 mL).
4. Once pork is cool enough to handle, using both a knife and your fingers, pull pork apart and chop into ½-inch (1-cm) pieces; add to a large bowl. Sprinkle bread crumbs over and toss to combine. Pour reduced braising liquid over; stir gently and set aside.
5. Fry bacon in a large skillet over medium-high heat; cook for 4 to 5 minutes or until bacon just begins to crisp. Remove with a slotted spoon to bowl containing pork mixture. Drain all but 1 tbsp (15 mL) bacon fat from pan and return to medium-low heat.
6. Cook onion for about 6 minutes or until translucent; stir in garlic, cook 1 more minute. Add cinnamon, cloves, nutmeg and allspice; stir in potatoes and remaining 1 tsp (5 mL) salt. Cook, stirring often, for 8 to 10 minutes, until potatoes are tender. Scrape mixture into bowl over pork and bacon; stir to combine. Check seasoning; adjust if necessary. Cover and refrigerate until completely chilled, preferably overnight.
7. For the crust, combine flour, butter, lard and salt in a food processor; pulse until butter and lard are pea-sized. Turn out onto counter and sprinkle with ¼ cup (60 mL) ice-cold water. Bring dough together with your hands, folding it over onto itself several times and flattening as you go. Divide into 2 pieces, one roughly one-third, and the other two-thirds. Wrap both pieces in plastic wrap and refrigerate for at least 1 hour or overnight.
8. When ready to assemble and bake, preheat oven to 400°F (200°C).
9. On a lightly floured surface, roll out smaller quantity of dough a scant ¼ inch (5 mm) thick; transfer to a 9-inch (23-cm) deep-dish pie plate. Trim dough leaving 1 inch (2.5 cm) of overhang. Fill with meat mixture and bring overhang up and over the edge of the meat; brush exposed dough with water.
10. If making a decorative top, roll out dough ⅛ inch (3 mm) thick; cut into as many pieces as you’re able to, using the cookie cutter of your choice. Arrange cut-outs in concentric circles overtop filling, being sure to brush bottom of each with a little water to adhere. Leave or cut out a 1-inch (2.5-cm) hole in centre.
11. Brush pastry with egg and bake in preheated oven for 30 to 35 minutes or until golden. Reduce temperature to 350°F (180°C) and bake for another 40 to 45 minutes or until deeply golden and filling is hot. Let rest at least 30 minutes before serving.