How to Make It
In a small skillet, toast the pine nuts over moderate heat, shaking occasionally, until golden, 3 to 5 minutes. Place in a large bowl and let cool completely.
On a lightly floured work surface, using a lightly floured rolling pin, roll the puff pastry to 1/8-inch thickness. Stamp out ten 4-inch rounds and ten 2 1/2-inch rounds. Transfer rounds to 2 baking sheets lined with parchment paper, and refrigerate.
Meanwhile, add the pork, milk, cranberries, apricots, pistachios, salt, and pepper to the bowl with the pine nuts, and gently mix with fingers until just combined. Form into ten 2-inch patties. Place a 4-inch dough round in a cupped hand. Top with a pork patty and a 2 1/2-inch round. Crimp the edges to seal, and transfer to a prepared baking sheet. Repeat with the remaining dough and pork patties, and refrigerate pies until firm, 1 to 8 hours.
Preheat the oven to 350°. Brush the pies with egg wash and, using the tip of a small knife, poke 3 slits in the top of each. Bake until puffed and golden, 40 to 45 minutes. Let cool slightly and serve warm.