Isabella Beeton,
Mrs. Beeton's Book of Household Management
(1907)
“ There are three varieties of roux: white, fawn, and brown; and this form of thickening is generally employed in making good sauces. It may be made in small quantities as required, or in larger quantities, which, if closely covered, will keep good for months. When roux is made for immediate use it should be allowed to cool slightly before adding the liquid to it. When using perfectly cold roux, the liquid should be added to it more gradually: in both cases the sauce must be constantly stirred until it boils, and then allowed to simmer until it attains the required consistency. ”
