This section is from the book "Miss Leslie's New Cookery Book", by Eliza Leslie. Also available from Amazon: Miss Leslie's new cookery book.
Cut up a quarter of a pound of the best fresh butter, and put it into a well tinned or enameled saucepan. Set it over a moderate fire, and melt it slowly, shaking it round frequently, and taking care to skim it well. When no more scum appears on the surface, let it settle a few minutes; then pour it off from the sediment at the bottom. Wash the sauce-pan or get another clean one. Return the melted butter to it, and set it again over the fire. Then dredge in gradually sufficient sifted flour to make it very thick and smooth, stirring it well after each addition of flour. Do not allow it to brown in the slightest degree, but keep it perfectly white to the last; simmering, but not actually boiling, and take care that there is no smoke about the fire.
To thicken white sauces, or soups, stir in a table-spoonful or two of this roux, pronounced too. In French cooking it passes for cream.
Browned thickening is made in the same manner; but with butter and browned flour, and is used for brown soups and gravies.
This is to enrich the taste and improve the color of gravies, stews, and soups. Mix a quarter of a pound of powdered white sugar with two ounces of fine fresh butter; and, having stirred them well together, put them into a saucepan over the fire, and simmer till it begins to froth; then diminish the heat a little. When its color becomes a fine dark brown, add two glasses of port wine, and three or four blades of mace, powdered. When it comes to a boil, take it off, and stir it into whatever you intend to color.
Another browning is mushroom catchup, or walnut catchup. They communicate a slightly acid taste. So also does French mustard. Stir it in at the last. Its tarragon flavor is very generally liked.
Sift some fine flour, spread it on a large dish, or clean tin-pan. Place it before the fire, so as to brown but not to scorch or burn. It will color first at the edges; therefore watch it, and keep it evenly mixed with the white flour from the centre. When all is nicely browned, set it to cool, and then put it away for use in a large clean bottle or jar, well corked. Flour may be browned in an oven, after baking is over, taking care to stir it well. - Have two dredging boxes. One for browned flour and one for white. It is convenient also to have dredging-boxes for powdered herbs. The cost of these boxes is very trifling, and it saves time and trouble to have things ready when wanted. A small sieve for powdered white sugar is indispensable.
This sauce is for fresh salmon or turbot, or sheep's-head fish. Also for salmon-trout, blue-fish, or the lake white-fish.
Put a large hen lobster into a hard-boiling pot of highly-salted water, that the animal may die immediately. Continue the boiling with a steady heat, and in about three quarters, or an hour, the lobster will be done. When cold, extract all the meat from the shell, and cut it into small bits. Pound the coral, or red substance, in a marble mortar, with some fresh butter, or plenty of salad oil; and a little cayenne. Add the coral to the cut-up lobster, and put the whole into a stew-pan, with some powdered mace and nutmeg, and a large table-spoonful of sweet oil. Divide into four bits a quarter of a pound of fresh butter, each bit rolled in flour. If your butter is not fresh and very good, omit it entirely and substitute a larger quantity of oil. As bad butter spoils every thing, never on any account, use it. Set the sauce-pan over the fire, and let it boil up once. Then take it off, and while very hot, stir in the beaten yolks of two eggs.
Crab sauce is made in the same manner. Prawn sauce also.
 
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