For the filling, combine ground pork, chopped woodear mushrooms (or any mushrooms), minced onion, garlic, shallots, green onion, 1 egg, fish sauce, black pepper, sugar, dark soy sauce, and MSG. Mix well. Thaw and roll out 4 sheets of puff pastry. Cut each pastry sheet into 9 equal pieces. Plop about 2-3 tbsp of the filling in the center of one pastry piece. Place another pastry piece on top and crimp the edges to close with a fork. Before baking, brush the top of each pie with egg wash and sprinkle with flaky salt. Bake at 390F for about 20 minutes, or until golden brown and crispy.
