Tartar sauce (French: sauce tartare; also spelled Tartare sauce in the UK, New Zealand, Australia, South Africa, and other parts of the Commonwealth) is a condiment primarily composed of mayonnaise and finely chopped capers. Tartar sauce can also be enhanced with the addition of gherkins, other varieties of pickles, and lemon juice as well as herbs such as dill and parsley.
Tartar sauce is based on either mayonnaise (egg yolk, mustard or vinegar, bitartrate, oil) or aioli (olive oil, garlic), with certain other ingredients added. In the UK, recipes typically add to the base capers, gherkins, lemon juice, and dill. US recipes may include chopped pickles or prepared green sweet relish, capers, onions (or chives), and fresh parsley. Chopped hard-boiled eggs or olives are sometimes added, as may be Dijon mustard and cocktail onions. Paul Bocuse described sauce tartare explicitly as a sauce remoulade, in which the characterising anchovy purée is to be replaced by some hot Dijon mustard.
History and etymology
Ultimately, tartar sauce gets its name from the Golden Horde, Mongols who invaded Europe in the 13th century, who were known to the locals as Tartars. This name comes from confusion over their allies the Tatars, because of whom the Europeans called Mongolia Tartary. This misnomer came from associating the name Tatar with the Greek mythological hell known as Tartarus.
The Mongols brought a tradition of finely minced meat, often eaten raw. That style of raw, minced meat made its way to Russia, then Hamburg, then the US with German immigrants. There it became known as Hamburg steak, a raw minced beef patty with onions and bread crumbs. This travelled back to Europe as steacke à l'Americaine, but as the novelty wore off gradually came to be known as steak tartare, and the sauce used on it as tartar sauce.