Homemade pasta seems intimidating, but it shouldn't be. This is an easy recipe, and can be made into any number of finished dishes. This one combines fresh pappardelle with prosciutto and some ingredients especially tailored for spring, with a subtle richness to bring it all together.
Combine the "00" flour, semolina, and salt on a countertop and mix well. Form a well in the center and add the egg yolks and olive oil. Using a fork, lightly whisk the eggs and olive oil.Slowly incorporate the flour from the inner part of the well into the egg mixture with the fork. When about ¼ of the flour is incorporated, use bowl scraper to fold in the remaining flour. (Note: If all the flour is not absorbed, just knead what is naturally able to work into the dough.) Knead for five minutes with your palms until a smooth dough is formed. The dough should not be tacky. Let the dough rest, covered at room temperature, for about 1 hour.
Divide the dough in half so that it is easier to work with. Temper it by beating it lightly with a rolling pin to flatten, dusting as necessary with flour. Roll out the pasta either by hand or by using a manual or electric pasta roller to very thin. If using a pasta maker, start with the widest setting and work to very thin (about an 8 or 9 setting). Dust with flour as necessary. Take the length of rolled-out dough and cut into 12-inch sections. Lay each section out on a countertop for several minutes to rest and lightly dry.
Clean fava beans and leeks. Cut away and discard the dark green part of each leek; slice white and pale green parts lengthwise through the center, then slice crosswise into 1-inch squares. Place leeks into a bowl of water. Toss in the water to clean and separate leeks. Place butter into a medium-sized saucepan placed over medium heat. Add leeks and a pinch of salt; melt butter and sweat leeks. Add a splash of water to ensure that leeks and butter do not brown. When leeks begin to soften, stir and add white wine. Add heavy cream, then raise heat and allow to gently simmer.Meanwhile, bring a large pot of generously salted water to a boil. Slice prosciutto into strips and set aside.
Cut pasta into ribbons: Dust each 12-inch section of cut pasta with semolina. Layer a few sections and loosely fold into a log. Slice the pasta into inch-wide strips. Separate each ribbon and then gather a few into bundles, rolling around finger. (You can also cut different shapes and ribbon pasta widths.)Taste warmed cream and leek mixture and season as needed. Spoon about 1½ C reduced cream and leek mixture into a wide sauté pan. Add fava beans and prosciutto. Drop fresh pappardelle into salted boiling water and cook until slightly undercooked, less than one minute. Add pappardelle into the sauté pan with a bit of pasta water and cook with the sauce. Toss gently. Adjust seasoning.
Spoon pasta into a wide bowl. Garnish generously with freshly grated Parmesan and serve hot.