Sauce allemande is the white version of brown sauce espagnole, and in spite of their German and Spanish names, both are French.
The classic sauce allemande is made with a velouté simmered with poultry or veal or fish stock and mushrooms until thick and reduced. Removed from the heat, four egg yolks, cream and add a knob of butter are liaised into the sauce, which is then slowly reheated and stirred until thick, then run through a sieve.
The great chef Marie Antoine Carême in his L’art de la cuisine française au XIXe siècle (1833) considered it a mother sauce, along with béchamel, espagnole and velouté. Escoffier renamed it sauce parisienne during the First World War.
Sauce poulette is sauce allemande with the addition of lemon juice and parsley. Originally it was served with a chicken fricassée (hence its name), but these days it’s usually made in a less fussy way by mixing egg yolks with cream and corn flour, slowly adding warm chicken broth and whisking until thick, then adding salt, pepper, parsley and lemon juice. It’s good on mussels or mushrooms.
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