Tartare sauce is a classic, which is used mainly to accompany any cold cooked fish.
Put the egg yolks in a mortar and pound with the pestle to make a smooth paste.
Season with salt and pepper.
Then incorporate the oil in a thin stream, stirring continuously with the pestle until well amalgamated.
When it is all incorporated, add the vinegar or lemon juice.
then the onion, chives and mayonnaise and season to taste.
Depending on your taste and how you're going to use the tartar sauce, you can vary the herbs:
Don't be misled by recipes that call for chopped sweet gherkins, capers, etc. They're a derivative of tartar sauce, but they're not the "original," if I may put it that way!
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