In a large mixing bowl, sift together the flour, salt, and baking powder. Cut in the shortening until the flour forms tiny balls. Add the egg and mix well, then add the milk and mix well again. Refrigerate for 2 hours. In a large skillet over medium heat, brown the meats. Add the onions and garlic, and cook until the onions are clear. Stir in the salt, pepper, butterbeans, and flour, and heat through. Preheat the oil to 350 degrees. Turn the pastry onto a floured surface and roll out to about ¼ inch thick. Cut the pastry into 5-inch circles, place one heaping tablespoon of the filling in the lower half of the shell, wet the inside edges with a little water, fold over, and press together to seal. Deep fry until golden brown, about 3 minutes.