Sauce gribiche
Sauce gribiche is a mayonnaise-style cold egg sauce in French cuisine, made by emulsifying hard-boiled egg yolks and mustard with a neutral oil like canola or grapeseed. The sauce is finished with chopped pickled cucumbers, capers, parsley, chervil and tarragon. It also includes hard-boiled egg whites cut in a julienne.
Classically, sauce gribiche may be served with boiled chicken, fish, calf's head, tripe, or cold terrine. Modern variations may see sauce gribiche paired with vegetables too such as asparagus, charred lettuce or leeks, or even served as a dip.