It might sound fancy, but making a roux (pronounced “roo”) is one of the simplest and most basic of French cooking techniques. Made by cooking equal parts fat (butter, oil, or bacon drippings) and flour, by weight, a roux is used to thicken creamy soups and sauces (like the sauce for macaroni and cheese) or to add a distinctive flavor and color to dishes such as gumbo.
2. Add 3 tablespoons all-purpose flour all at once and begin whisking (B). (A wooden spoon may also be used.)
3. Stir continuously for about 2 minutes, to cook out the raw flour taste. The roux will at times be clumpy (C) or foamy (D), but eventually a smooth paste the consistency of wet sand will form (E).
This white roux makes a great base for homemade macaroni and cheese, and will give medium body to about 1 pint of liquid. If desired, lower the heat to medium-low and keep cooking the roux, stirring occasionally. The longer it cooks, the darker it will become. It will lose some of its thickening power, but its nutty flavor will be enhanced.