Step 1Pour the flour onto a work surface, shape it into a mound and scoop out a deep hollow in its center. Break the eggs into the hollow. Beat the eggs lightly with a fork for about 1 minute. Draw some of the flour over the eggs with the fork, mixing it in with the eggs until the eggs are no longer runny. Draw the sides of the mound together with your hands, pushing a bit of the flour to the side and reserving it.
Step 2Work the eggs and flour together, using your fingers and the palms of your hands, until you have a smooth dough. If it is still moist and sticky, work in more flour. To test the dough to see whether it has enough flour, rinse your hands and dry them, then press your thumb deep into the center of the dough mass. If it comes out clean, no more flour is needed. If it comes out sticky, add more flour from the reserved portion.
Step 3Knead the dough in a pasta maker or by hand, using the heel of your palm to press down on the dough, then turning and repeating the motion until you have kneaded the dough for 8 minutes and it is very smooth.
Step 4Cut the dough ball into 12 equal parts and run through a pasta machine set to the desired thickness. Proceed according to manufacturer's instructions, or cut by hand. For tagliatelle, the ribbons should be about one-fourth inch wide; for pappardelle, three-fourths inch wide. When the thinned strips of pasta are dry enough to cut but still soft enough to bend without cracking, fold them up loosely along their length, making a flat roll about 3 inches wide at its sides. With a cleaver or similar knife, cut the roll into ribbons. Cut parallel to the original length of the pasta strip so the tagliatelle will be the full length of the strip.
Step 5Fill a large pot with water and bring to a boil. Add salt and the pasta and cook for 2 to 4 minutes, until tender but still slightly firm to the bite. Drain and toss with sauce.