Wash the asparagus well, cut the tips off, place them in a saucepan with a bit of oil and fry lightly until golden, stirring with a wooden spoon for 3-4 minutes. Add the tomato sauce, season with salt and cook for 20-25 minutes covering with a lid; from time to time check that the sauce does not thicken too much.Eventually add a bit of water or broth to prevent its thickening. Cook the pasta in a saucepan with plenty of boiling salted water. Drain it al dente; pour it in the serving dish, previously sprinkled with the parmesan cheese and season with the asparagus sauce. Serve warm.