Place four ounces of butter in a pan on the fire, and as soon as the froth falls, skim it carefully, and leave it on the fire until it begins to brown slightly, then let it settle and pour off the clear part; season with salt, pepper, and lemon-juice, and throw this over fish or any other article, after straining it through a fine strainer.
A one-ingredient French sauce that lives or dies on a thirty-second window of attention. Ranhofer's version is unusual in that he pours off the clear fat and leaves the browned solids behind, giving a nuttier clarified butter rather than the speckled brown butter most cooks make today.
Charles Ranhofer spent some thirty years as chef at Delmonico's in New York, and The Epicurean (1894) is essentially the working repertoire of that kitchen set down in French classical order — which is why a book aimed at professional chefs, caterers and stewards devotes a whole section to hot and cold butters, the small compound and cooked butters that a French brigade treated as basic equipment rather than as recipes. Beurre noisette sits on a continuum with beurre noir, taken further to a dark brown and traditionally finished with vinegar and capers for skate; the noisette stage is the gentler cousin, and it is often said to have been a common accompaniment to sautéed sole, trout and brains. Ranhofer's instruction to pour off the clear part and discard the sediment reflects a period preference for a limpid sauce; the modern habit of keeping the toasted solids in the pan, common in both restaurant and home cooking now, gives more flavour and a cloudier result.