In a medium bowl, combine flour and salt. Dice the butter and cut into the flour using a dough blender, forks, or your fingers. Using a fork, slowly mic in 4 tablespoons water. If needed, add up to 2 tablespoons more water to bring dough together. Knead just until smooth, form into a ball, wrap in plastic, and refrigerate at least 30 minutes.
In a large skillet, drizzle oil over medium heat. Once heated, add pork and beef. Season with salt and pepper. Cook, breaking up the meat into small pieces, until browned. Stir in the onion, garlic, parsley, allspice, cinnamon, and cloves. Cook, stirring often, until onions are softened, 5-10 minutes. Stir in the stock and cook until reduced, another 5-10 minutes. Add enough breadcrumbs to absorb the stock. Adjust spices as needed, remove from heat, and let cool.
Preheat oven to 350 degrees F and butter a pie pan.
Split the refrigerated pie crust into 2 pieces, one piece a little larger than the other. Roll the larger piece into a circle wide enough to cover the bottom and sides of pie pan. Place in pie pan and evenly add cooled meat filling. Roll out the smaller piece to cover the top. Trim excess crust and seal the edges. Cut out a hole in the center of the crust to release steam while baking.
In a small bowl, beat egg yolk with water. Brush over top of pie. Bake in preheated oven until top is golden, 25-30 minutes. Let cool 5-10 minutes before slicing and serving.