In a bowl, blend together flour and 1/4 tsp (1 mL) each salt and pepper. Using a box grater, grate in frozen shortening and mix to coat evenly. Sprinkle 1/4 cup (60 mL) ice water overtop, 1 tbsp (15 mL) at a time, and mix with hands until dough just holds together. Press dough into a disc shape, wrap with plastic wrap and refrigerate, 20 min.
Meanwhile, in a large skillet, heat oil over medium-high heat. Add pork and beef and sauté until cooked through, about 7 min. Drain excess fat then stir in broth, potatoes, onion, garlic, cinnamon, allspice and remaining salt and pepper. Reduce heat to medium and simmer, stirring occasionally, until most of the liquid evaporates, about 30 min. Mix in breadcrumbs and thyme. Set aside to cool completely.
Preheat oven to 375°F (190°C). Arrange four 5-in. (12-cm) pie plates on a rimmed baking sheet. On a lightly floured surface, roll out dough to a 1/8-in. (3 mm) thickness. Cut out 4 circles that are 6 in. (15 cm) in diameter and use any leftover pastry to create decorative leaves for.
Divide filling evenly among pie plates, and smooth out and place a circle of dough overtop. Press and crimp edges of pastry and pie plate together to seal. Place decorative pastry leaves on tops, brush tops with egg, cut in a few steam vents and bake until golden brown, about 45 min.
The filling and pastry can be made up to a day in advance and refrigerated.