Preparation

Make the broth

• Wash the chicken, veal bones, beef, and vegetables under cold running water. Put all of the broth ingredients, except the salt, in a 10-quart pot and add 6-1/2 quarts (26 cups) of cold water. Partially cover the pot and bring to a simmer over medium heat. As soon as the water begins to bubble, reduce the heat to low and, with a fine-mesh skimmer or a large spoon, skim off and discard any foam that has risen to the surface. Partially cover the pot and simmer gently until the broth is flavorful, about 2-1/2 hours. Add 1 Tbs. salt during the last few minutes of cooking.

  Remove the chicken and discard or save the meat for another use. Using a slotted spoon, discard the remaining solids from the broth. Strain the broth through a fine strainer into a large bowl. Line the strainer with a clean thin kitchen towel or cheesecloth and strain the broth again into another large bowl. You should have about 6 quarts of broth. Transfer the broth to storage containers and refrigerate overnight. Remove the fat and reserve the broth.

Make the filling

• Melt the butter in a 10-inch skillet over medium heat. Add the pork and cook, stirring, until lightly golden and cooked through, about 4 minutes. Increase the heat to high, pour in the wine, and stir until it is almost evaporated, 3 to 5 minutes. Let cool slightly.

  Transfer the pork and its juices to a food processor. Add the prosciutto and mortadella and pulse until the mixture is very finely chopped (but not puréed).

  Transfer the filling to a medium bowl and add the Parmigiano, nutmeg, egg, and 3/4 tsp. salt. Mix well. (The filling should be moist and just a little sticky.) Cover the bowl with plastic wrap and refrigerate.

Make the pasta dough

• On a large wooden board or other work surface, shape the flour into a mound. Using your fingers, make a round well in the center of the flour. Carefully crack the eggs into the well, making sure they don’t escape the walls of the well. Lightly beat the eggs with a fork. Begin to incorporate flour into the eggs with the fork, starting from the inner rim of the well, until about half of the flour is incorporated and a soft dough begins to form.

  With a dough scraper, push all of the remaining flour to one side of the board. Scrape off and discard the bits and pieces of dough attached to the board. Wash and dry your hands. Begin adding some of the flour you have pushed aside into the soft dough, kneading it gently with the heels of your hands as you incorporate the additional flour and the dough becomes firmer. Keep the board clean and dust it with flour as you knead to prevent the dough from sticking. After kneading for 8 to 10 minutes, the dough should be smooth, elastic, and just a little sticky.

  Press one finger into the center of the dough; if it comes out barely moist, the dough is ready to be rolled out. If the dough is still quite sticky, add a little more flour and knead it for 2 to 3 minutes longer until soft and pliable.

  Wrap the dough in plastic wrap and let it rest at room temperature for 20 to 30 minutes.

Roll the pasta

• Unwrap the dough and knead it for a minute or two. Set the rollers of a pasta machine at their widest. Cut off a piece of dough about the size of a small lemon and flatten it with the palm of your hand to about 1/2 inch thick. As you work, keep the rest of the dough wrapped in plastic. Dust the piece of dough lightly with flour and run it through the machine. Fold the rolled dough in half and run it through the machine again, pressing it with your fingertips into the rollers . Repeat this step 4 or 5 times, dusting the dough with flour if it becomes sticky, until smooth and elastic.

  Change the rollers to the next setting down and roll out the dough without folding. Repeat rolling the sheet of dough (without folding) through the pasta machine, decreasing the settings until the pasta is 1/8 inch thick. On a floured wooden board, cut the dough into 1-1/2-inch squares. Keep the squares covered with plastic as you shape the tortellini.

Shape the tortellini

• Put about 1/8 tsp. of the filling in the center of a pasta square. Bring one corner over the filling toward the corner diagonally opposite and fold into a triangle. Press around the filling to seal. Bend the tortellino around your finger with one corner slightly overlapping the other and press to seal. The tortellino will look like a crown. Transfer to a large rimmed baking sheet lined with a clean kitchen towel. Arrange the tortellini in a single layer without letting them touch (you’ll need 2 to 3 baking sheets) and cover with another clean towel.

  Repeat the filling and shaping with the remaining pasta and filling.

Cook and serve the tortellini en brodo

• You can make as many or as few servings as you like. For each serving, you’ll need 1-1/2 cups of broth and 14 tortellini. Bring the broth to a boil in a large pot over medium heat. Gently drop the tortellini into the pot. Cook until they rise to the surface and are tender but still firm to the bite, 2 to 3 minutes for fresh, 4 to 5 minutes for frozen. Remove the pot from the heat. Ladle the tortellini and broth into serving bowls, sprinkle with grated Parmigiano, and serve immediately.

Make Ahead Tips

The broth may be refrigerated for 3 days or frozen for up to 3 months. The filling may be made and refrigerated for up to 2 days or frozen for up to 1 month. The uncooked tortellini can be refrigerated, loosely covered with a towel, for up to 1 day. Or freeze the tortellini on the baking sheets; then transfer to freezer bags and freeze for up to 3 months.