Mound the flour on a clean counter and create a deep well in the center.
Crack the eggs into the well, add salt and olive oil if using.
Beat the eggs gently with a fork, gradually incorporating flour from the inner wall until the mixture thickens.
Use your hands to bring the mixture together into a shaggy dough.
Knead the dough for 8–10 minutes until smooth and elastic.
Wrap the dough in plastic and let it rest 20–30 minutes at room temperature.
Divide the dough into portions, flatten and roll each piece to about 1–2 mm thickness with a machine or rolling pin.
Fold and cut the rolled dough into tagliatelle (6–8 mm wide) or your desired shape.
Shake strands to separate and dust with semolina or flour to prevent sticking.
Boil a large pot of well-salted water and cook the fresh pasta 2–4 minutes until al dente; reserve a little pasta water.
Drain the pasta, toss with butter or your chosen sauce and a splash of reserved pasta water, then serve immediately.