Heat the oil, half of the finely chopped parsley and 2 crushed garlic cloves (do not let them get too hot) until the scent rises. Add tomatoes and chili peppers and season with salt. Cook the spaghetti in salted water al dente and drain. Add the remaining parsley and the last clove of garlic to the sauce. Put the spaghetti in a preheated bowl and pour the sugo over it, stir and serve.