This section is from the "The French Cook" book, by Louis Eustache. Also see Amazon: The French Cook.
Make a marinade, in which stew the salmon. When it is done, pick off the scales carefully. Pour the marinade oyer the salmon to keep it hot. Then make a sauce mate-lotte in the following manner: put a good bit of butter and two spoonfuls of flour into a stew-pan, and make a roux. When it begins to colour, throw four or six onions into your roux, and let them melt: keep Stirring with a wooden spoon. Then moisten with a bottle of red wine; add a few spoonfuls of the marinade in which you have stewed the salmon, some trimmings of mushrooms, a bunch of parsley and green onions well seasoned, and a small piece of glaze; season the whole, and put a little sugar to correct the acidity of the wine; skim the grease, and keep the sauce thick. In case it should not be thick enough to mask with, add a small bit of butter kneaded with flour, a quarter of a pound of fresh butter, some essence of anchovies, the juice of a lemon, and some salt and pepper. Drain your fish, and mask it with the sauce, after having strained it through a tammy.
This is an entremet which is recurred to on economical principles, when there is any salmon left. Let it cool, and cut it nicely into hearts, or square lozenges. Decorate these with fillets of anchovies, pickled cucumbers, fine capers, and chopped eggs, to which add a few hearts of lettuce. Then make the sauce as follows; if you should have some jelly, make a kind of mayonaise. Put three Spoonfuls of oil, one spoonful of vinegar, with an equal quantity of jelly seasoned with pepper, salty and chopped ravigotte. Beat all these over ice, till they are of a white colour, and decorate your salad with this mayonaise, and a few lumps of jelly, cut of different shapes. Avoid making any decorations that are liable to tumble down. A plain good salad is eaten in preference to any other. Grand decorations are intended to ornament the centre of the table, whereas what is to be eaten must be plain and good. Above all things, avoid introducing artificial colours. Nature has supplied you with nasturtium, red and white beet-root, beans of two colours white and green, chervil, Tarragon, burnet, etc.; besides, you have white or yellow omelettes. Never put any fish into a salad of fowl, for if the fowl tastes of fish, what will you have your salads maigres taste of? In summer-time, you have asparagus, artichoke-bottoms, cauliflowers, etc.
Salmon is also cooked in various other ways, which ought not to be done. This fish being oily, will not admit of so many metamorphoses. I have seen salmon-pies sent to table, petty patties, and scollops of salmon in paper cases, croquettes ditto, and bonne morue, all which entrees are good for nothing ; and the best proof of the truth of this assertion is, that no one will ever taste them. If, notwithstanding you would wish to try, the process is the same as for dressing turbot, or haddock. However, if you will follow my advice, you will never attempt any other entrees but those herein described.
See No. 29, page 89.
The same process as above. Make a marinade, and pour it into a vessel large enough to contain the fish, which cover with buttered paper, to prevent its getting too high a colour. Baste frequently with the marinade. When the sturgeon is done, have the sauce made as No. 29, page 89, and use it to mask the fish.
Boil the sturgeon in salt and water. When it is done, drain and mask it with the following sauce: reduce in a small stew-pan four spoonfuls of elder vinegar. When it is half reduced, put in six spoonfuls of veloute, or rather a quantity proportionate to the size of the fish, half a spoonful of cavice, a quarter of a pound of butter, and some salt and pepper. Work this sauce well; drain the fish, and mask it with the sauce. In order to keep it thick and white, mix with it a little thick cream.
WHEN you have some roasted sturgeon returned, keep it to make a blanquette. Pare some round pieces nicely, of the size of half-a-crown, and put them into a sauce a blanquette, to which you add a little chopped parsley, and the juice of a lemon. This blanquette is sent to table like all others in a vol au vent, or a casserole au ris.
If you have any sturgeon left, that is still very fresh, make a blanquette with peas, which not requiring to be highly seasoned, will admit only of fish which is extremely sweet. After having simmered the peas as they are always prepared for the second course, take three spoonfuls of sauce tournee, and reduce it with four spoonfuls of the peas: add a very small bit of sugar. When your sauce is very thick, put to it a thickening of two yolks of eggs, then put the sturgeon to it, and serve either in a vol au vent, or in a bordure of potatoes. Observe, that in this entree the seasoning must be very mild.
 
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