Clarified butter is best for this purpose; but if you have none ready, put some fresh butter into a stewpan over a slow, clear fire; when it is melted, add fine flour sufficient to make it the thickness of paste; stir it well together with a wooden spoon for fifteen or twenty minutes, till it is quite smooth, and the color of a guinea: this must be done very gradually and patientlv; if you put it over too fierce a fire to hurry it, it will become bitter and empvreumatic: pout it into an earthen pan, and keep it for use. It will keep good a fortnight in summer, and longer in winter.
A large spoonful will generally be enough to thicken a quart of gravy.
This, in the French kitchen, is called roux. Be particularly attentive in making it; if it gets any burnt smell or taste, it will spoil everything: it is put into. When cold, it should be thick enough to cut out with a knife, like a solid paste.
It is a very essential article in the kitchen, and is the basis of consistency in most made-dishes, soups, sauces, and ragouts; if the gravies, etc. are too thin, add this thickening, more or less, according to the consistence you would wish them to have.
In making thickening, the less-butter, and the more flour you use, the better; they must be thoroughly worked together, and the broth, or soup, etc. you put them to, added by degrees: take especial care to incorporate them well together, or your sauces, etc. will taste floury, and have a disgusting, greasy appearance: therefore, after you have thickened your sauce, add to it some broth, or warm water, in the proportion of two table-spoonfuls to a pint, and set it by the side of the fire, to raise any fat, etc. that is not thoroughly incorporated with the gravy, which you must carefully remove as it comes to the top. This is called cleansing, or finishing the sauce.
Half an ounce of butter, and a table-spoonful of flour, are about the proportion for a pint of sauce to make it as thick as cream.
The fat skimmings off the top of the broth-pot are sometimes substituted for butter; some cooks merely thicken their soups and sauces with flour.