General Remarks on Soups
Utensils and Fire.—The remarks on [pages 1] and [2] concerning the utensils and fire for making stock, apply also to the preparation of soups from stock.
To thicken soups with flour only.—Mix flour or cornflour with a little cold water, milk or stock until perfectly smooth. Add more water or milk. Strain. Pour slowly into the soup, which should be nearly boiling. Let it come to a boil. Continue boiling for ten minutes (stirring all the time), or it will taste of flour. About one table-spoon of flour should be used to thicken each quart of stock.
To thicken soups with butter and flour (roux).—Melt some butter. Skim it till quite clear. Pour it into an earthenware sauce-pan, and add to it its weight in flour. Work with a wooden spoon until perfectly smooth. Stir over a fire for a few minutes. Then put it in a moderate oven. Stir occasionally, and be very particular that it does not colour or burn. It should be left in the oven from thirty to forty-five minutes. This thickening, which is called white roux, is used for white soups. Brown roux for brown soups is made in the same way, but is left in the oven until slightly coloured. It will keep for some time.
When adding roux to soups it is best first to melt it in a small sauce-pan, to thin it with a little hot stock, and then to add it gradually to the soups.
If the roux has not been prepared beforehand, the quantity required can be made in a short time by cooking the flour and butter together in a sauce-pan for five minutes for white roux or longer for brown roux. It should be stirred all the time.
A heaping table-spoon (or more) of roux should be added to every quart of soup to be thickened.
Cornflour and roux.—The advantage of roux over cornflour is that the flour used in preparing the roux having been already cooked, it is not necessary to continue boiling the soups to which it is added, whereas cornflour being raw, the soups thickened by it must be boiled for some little time.
To colour soups.—The colour of soups can be deepened by using caramel colouring, or glaze (see next page) (which will also add to their flavour).
Caramel colouring.—Put half a pound of brown or white sugar in an iron sauce-pan, with a table-spoonful of water. Stir over a very gentle fire until it turns a deep, rich brown colour. Add half a pint of boiling water. Let it simmer very gently for twenty minutes. Allow it to get cold. Put it into bottles and cork. This makes an excellent and tasteless colouring, but it must be carefully made. The rich brown colour comes from slow and gentle cooking. If it is burnt and black it is useless.