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The Very Un-Dutch History of Hollandaise Sauce Despite its name, there is general agreement that Hollandaise was born in France and was originally known as Sauce Isigny, after a town in Normandy famous for its butter and cream. What provoked the name change is uncertain, and the alternate name of Sauce Isigny is still listed in French reference books.
A Hollandaise is made from egg yolk, which contains a large quantity of the emulsifying agent lecithin, which is a natural emulsifier. This is used to combine and emulsify warm butter and a small amount of water, lemon juice or vinegar.