Peel the onion, rinse it and chop it finely. Clean the anchovies, boning them and removing the head, rinse them and dry them with a clean towel, then chop them up. Cook the pasta in plenty of boiling salted water.In the meanwhile in a saucepan heat the oil, add the onion with the lightly crushed garlic and fry until soft but not golden. Remove the garlic, add the anchovies and the chopped parsley.Season with salt and pepper and simmer for 2-3 minutes, mix delicately with a wooden spoon. Drain the pasta al dente, mix it with the anchovy sauce. Serve warm.