This section is from the book "The Epicurean", by Charles Ranhofer. Also available from Amazon: The Epicurean, a Complete Treatise of Analytical and Practical Studies on the Culinary Art.
Lift the fillets from a blackfish; remove the skin by laying the black side on a very level table or board; press down on the fish with the left hand, while with the right pass a knife between the skin and flesh. Divide the fillets into thin, lengthwise slices; marinate them in salt. sweet oil with minced onions, lemon juice, and tarragon leaves; two hours later drain them on a cloth, flour over, and dip in a good frying batter (No. 133); plunge them into hot fat, and cook slowly till a fine color, then drain, salt, and dress them on napkins with sliced lemon around; serve a tomato sauce (No. 549) separately.
Remove the fillets from sufficient blackfish leaving on the black skin; divide each fillet into two pieces. Cover the bottom of a sautoir with butter, chopped shallots, and onions, and chopped mushrooms; lay on top the pieces of blackfish, and a branch of parsley, and moisten with a court bouillon (No. 38), let boil slowly for six minutes, then remove the sautoir on a very slow fire; when done lift out the fish with a spatula, suppress the black skin, and dress it on a dish. Garnish with handsome mushroom heads, oysters, and parsley sprigs; strain the broth, reduce it to a half-glaze, and thicken it with a pint of reduced veloute sauce (No. 415). Finish it away from the fire with butter, lemon juice, and a very little finely shredded chives.
Cook a whole blackfish in a mirepoix stock with white wine (No. 419), drain the stock after the fish is done, strain, and reduce it with the same quantity of veloute sauce ( No. 415), adding chopped up shallots; thicken the sauce with raw egg-yolks, cream, fresh butter, and fish glaze (No. 399); strain it again through a tammy and finish with chopped parsley. Range the fish on a dish, garnish around with potato croquettes (No. 2782), and branches of parsley, sending the sauce to the table in a separate sauce-boat.
 
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