Boudins of Kingfish a la Poniatowski

A quenelle forcemeat shaped into small sausages, poached in paper, crumbed in egg and fried — Delmonico's technique at its most fussy, but nothing in it is beyond a modern kitchen with a food processor.

• The hinge: poach gently, never at a rolling boilThe hinge: poach gently rather than at a hard rolling boil. Ranhofer says "boiling salted water," but a violent boil will swell and split the forcemeat inside its wrapper, so water held just below the boil is the safer reading; the boudins need only a few minutes at this size.
• KingfishThis is the Atlantic northern kingfish (a drum, Menticirrhus saxatilis), a common New York market fish in the 1890s and rarely sold today. Any lean, firm white fish works for a quenelle forcemeat: whiting, hake, haddock, pollock or cod.
• Quenelle forcemeat (No. 90)Ranhofer's fish quenelle forcemeats are generally raw fish pounded with a panada, butter, egg and cream, then sieved; check No. 90 for the exact proportions. A food processor can stand in for the mortar, provided everything — fish, bowl, blade, cream — is thoroughly chilled, or the mixture will break.
• Truffles"An eighth of its quantity" is not specified as weight or volume; read as volume it comes to roughly 2 tablespoons chopped truffle per cup of forcemeat. Preserved black truffle or truffle peelings are the closest practical stand-in; truffle oil is not, as it adds aroma without the texture the chopped pieces give.
• Buttered paperButtered parchment, rolled around each boudin like a cracker and twisted at both ends, does exactly what the original intends. Twist tightly enough to compact the forcemeat but not so tightly that it has nowhere to expand.
• FryingClarified butter is specified because whole butter's milk solids blacken before the egg coating sets. Fry only until pale gold, a minute or two a side — the boudins are already cooked through from the poaching, and the second cooking is purely for color and crust.
• Polish sauce (No. 524)Ranhofer's sauce polonaise here is not necessarily the familiar restaurant "polonaise" of browned butter, crumbs and chopped hard egg; look up No. 524 before assuming which preparation is meant.
• Yield and serviceAllow several boudins per person as a small entrée and scale to the amount of forcemeat you actually make rather than to a fixed count. The folded napkin on the platter is there to absorb butter; a warmed dish lined with paper does the same job.