You will need a small roasting pan; a meat grinder with coarse grinding plate; a pasta-rolling machine; a 1-inch- diameter round pastry or cookie cutter; a narrow pastry brush; trays or baking sheets lined with floured parchment or kitchen towels.

To make the filling: Preheat oven to 425 degrees. Cut the pork shoulder into 2-inch pieces, trimming away any excess fat or cartilage as you go. Put the meat in the small roasting pan along with the onion, carrot, celery, pancetta, porcini, and rosemary. Spread the tomato paste on the meat and vegetables, and toss to coat. Pour the hot stock into the pan.  

Roast the meat and vegetables, uncovered, until the meat is brown and tender and the pan juices have reduced to a thick gravy, about 1 hour. (If the meat is tender and the juices are still too thin, remove the pan from the oven and reduce on top of the stove.)

Let the meat, vegetables, and juices cool. Toss in the cubes of mortadella and run the entire mixture through the meat grinder into a large bowl. Run day-old bread through the grinder to clean out the last bit of meat (and catch it in the bowl). Beat the egg with a pinch of salt, and pour over the meat, along with the grated cheese, nutmeg, and bread crumbs. With your hands, work everything together to make a smooth stuffing.  

To make the anolini: Cut the dough in six equal pieces; work with two pieces of dough at a time, and keep the others covered. Roll one piece of dough through the pasta machine at progressively wider settings, always keeping it lightly floured, until you’ve created a long strip, as wide as your machine allows, and a little less than ⅛ inch thick. Lay it out on the work surface. Roll out the second piece of dough to a strip of the same size.  Lay one strip in front of you. Mark where you will be making the anolini by lightly pressing the 1-inch cutter on the dough—don’t cut through it—fitting as many outlined circles on the strip as you can.

Scoop small portions of the filling—⅓ to ½ teaspoon—and mount them in the center of all the circles. With the pastry brush (or your fingertip) dipped in water, lightly moisten the rim of the outlined circle around the filling mounds. Lay the second strip of dough over the first, gently stretching and draping it to cover all the mounds. Now center the cutter over each filling mound, and press it firmly, cleanly slicing through both layers of dough and cutting out the anolini. Pull away the excess dough to separate individual pieces, lightly dusting with flour as needed. Press the edges of the pasta circles together if they have gaps. Arrange the anolini in a single layer on a floured and lined tray, and cover them lightly.  

Now roll out and fill the remaining pieces of pasta dough, in pairs, to make two more batches of anolini, in the same way. Anolini that you will cook soon can be left on the tray, lightly covered. Freeze anolini for future use right on the trays. When they are frozen solid, transfer them to freezer bags, packed airtight and sealed.  To cook and serve anolini in broth for six, you will need about a hundred anolini, so everyone gets at least fifteen in a bowl of soup. (Of course, you can vary this number, depending on the size of your pasta pieces, the appetite of those you are feeding, and what else you’ve prepared for the meal.)  

Fill a large pasta pot—preferably with a wide diameter, so the anolini won’t be crowded—with at least 6 quarts well-salted water, and bring to the boil. At the same time, heat the Chicken Stock in another pot, so it is just simmering. Have your soup bowls warm and ready for filling. With the pasta water at a full rolling boil, spill in all the anolini, stir well, cover the pot, and return the water to the boil over high heat. Give the anolini another good stir, and let them cook for a quick minute, just until they’re barely al dente. Check one for doneness—the thickest part of the pasta should still be slightly resilient, since the anolini will continue to cook and soften in the brodo.

Turn off the heat and, with a big spider or other strainer, scoop out hot anolini, let them drain for a second, and spill fifteen to twenty into each of the warm soup bowls. Quickly ladle hot broth into each bowl (1½ to 2 cups a serving), and sprinkle over each a heaping spoonful or two of grated cheese. Serve each bowl of anolini in brodo while piping hot, with more grated cheese passed around the table.  If you want to serve the soup right at the table, bring out the pot of hot Chicken Stock and set it on a trivet, then drain the anolini and divide them among the soup bowls in the kitchen. Bring the bowls filled with anolini to the table, add the Chicken Stock, and serve.