Open up each anchovy and pull the spine and all the bones away. Remove the heads. Rinse the fish under cold running water and pat dry with kitchen paper.
Place the anchovies in a non-metallic dish, pour over the vinegar and add a pinch of salt. Cover and leave to marinate in the refrigerator for at least 2 hours until the fish is no longer translucent. Rinse again and pat dry.
Mix together the oil, garlic and chilli in a dish, then add the anchovies, cover and marinate in the refrigerator overnight. Serve with a little of the oil and the parsley scattered over.