Recipe Instructions For the Tortellini Pasta Dough: Mound 3 1/2 cups of the flour in the center of a large wooden cutting board. Make a well in the middle of the flour and add the eggs and the olive oil. Using a fork, beat together the eggs and oil and begin to incorporate the flour, starting with the inner rim of the well. As you expand the well, keep pushing the flour up from the base of the mound to retain the well shape. The dough will come together when half of the flour is incorporated. Start kneading the dough with both hands, using the palms of your hands. Once you have a cohesive mass, remove the dough from the board and scrape up and discard any leftover bits. Lightly re-flour the board and continue kneading for 6 more minutes. The dough should be elastic and a little sticky. Wrap the dough in plastic and allow to rest for 1 hour in the refrigerator. For the Tortellini Filling: In a Dutch oven or heavy-bottomed, large saucepan, heat the butter and oil until it foams and subsides. Add the turkey, veal and pork shoulder and cook over high heat, stirring occasionally, until the meat is well-browned and begins to release some of its juices. Add the prosciutto and mortadella and cook for 5 minutes more. Remove from heat and allow to cool. Place in a food processor and mix to combine. Add the egg and the Parmigiano-Reggiano and mix well to combine. Season with salt and pepper, to taste, and add at least 1/4 teaspoon freshly grated nutmeg and mix again. Set aside in the refrigerator until ready to use. Roll the pasta into sheets using a pasta machine. For the desired pasta sheet thickness, gradually pass the dough through the settings starting with the widest and continuing to the number 9 setting. With a pasta cutter or a knife, cut the pasta into 1 1/2-inch squares. Place 3/4 teaspoon of filling in the center of each square. Fold into triangles, press out any air around the filling, and press to seal the edges. Bring the points of the long side together to form a ring, and seal between your fingers. Set the tortellini aside on a sheet pan, wrap well with plastic wrap and refrigerate. Unused tortellini may be stored frozen for up to 2 months. (Makes 1 1/4 pounds) For the Brown Chicken Stock: In a large, heavy-bottomed saucepan, heat the oil until smoking. Add the chicken bones and scraps and brown all over, stirring to avoid burning. Remove the chicken parts and reserve. Add the carrots, onions and celery and cook until soft and browned. Return the chicken bones to the pot and add 3 quarts of water, the tomato paste, peppercorns, and parsley, stirring to dislodge the browned chicken and vegetables bits from the bottom of the pan. Bring almost to a boil, reduce to a simmer and allow to cook at a low simmer for 2 hours, until reduced by half, occasionally skimming excess fat. After cooking, remove from heat and strain out all solids, pressing them with the bottom of a ladle to extract out all liquids. Bring the brown chicken stock to a boil. Add the tortellini and cook for 8 to 10 minutes, until all the tortellini are floating to the top of the pot. Ladle equal portions of tortellini into 4 warmed pasta bowls. Ladle the hot broth on top of the tortellini, top with grated Parmigiano. This recipe yields 4 servings.