To make the pasta: Sift together and then mound 2 1/4 cups of the flour and a pinch of salt in the center of a large wooden cutting board. Make a well in the middle of the flour and add the eggs. Using a fork, beat together the eggs and the wine, 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. Knead for about 15 minutes, adding any of the remaining flour, if necessary to create a cohesive mass. Once you have a cohesive mass, remove the dough from the board and scrape up and discard any leftover bits. Lightly reflour 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 30 minutes at room temperature. After the dough has rested, use a sharp knife to cut the dough into medium pieces. Put through a pasta machine and cut into 3-inch strips.Using your thumb and forefinger, shape these pasta pieces into farfalle, or butterfly shaped pasta, squeezing at the center to form to wider sides, then flattening both sides to resemble wings. Repeat with the remaining dough. Set the farfalle on a baking sheet dusted with semolina flour and cover with a damp kitchen towel until ready to cook.
Bring 6 quarts water to a rolling boil and add 2 tablespoons salt.
Using a damp cloth, carefully clean the porcini mushrooms. Slice the mushrooms into medium size pieces.
In a 12 to 14-inch saucepan, heat the oil until hot but not smoking. Add the onion and garlic, and cook until soft and light golden brown, about 5 minutes. Add the sausage and cook until golden brown, about 5 to 7 minutes more. Add the mushrooms, mixing well to combine, and season, to taste. Add the tomatoes and their juices and the wine, salting lightly as you add. Cover, and let cook over medium heat until the tomatoes soften and exude more juices, about 15 to 20 minutes, stirring occasionally.
Add the pasta to the boiling water. Cook until tender but still al dente, about 7 to 8 minutes. Drain well, reserving 1/2 cup of the cooking liquid. Add the pasta to the sausage mixture and toss over high heat until well combined. Add some of the pasta cooking water, 1 tablespoon at a time, if the pasta is too dry. Sprinkle with parsley and Parmigiano. Serve immediately in warmed pasta bowls with a chunk of Parmigiano on the side for grating.
Recipe courtesy of Mario Batali