Chop the onion very finely. Sprinkle with lemon juice, leave to marinate.
Drain the oil from the cod liver. Mash the cream cheese with a fork, add the liver, mix well until smooth. Add onion, salt and pepper.
Season with mayonnaise. Store in the refrigerator until serving.
Very tasty with olives, dried tomatoes, capers and rye bread. Season with mayonnaise. Store in the refrigerator until serving.
It can be served with serving spoons for those who do not use bakery products.