How to Make Roux, Step-by-Step
Roux (pronounced "roo") is a thickening agent for soups and sauces with roots dating back more than 300 years in French cuisine.
Made by cooking a flour and oil paste until the raw flavor of the flour cooks out and the roux has achieved the desired color, a properly cooked roux imparts silky-smooth body and a nutty flavor while thickening soups and sauces.
1. Roux can be made with a variety of oils and animal fats. They are commonly made with vegetable oil, olive oil, or clarified butter, but can also be made with bacon grease or other rendered fats. Since an oil-based roux will separate as the flour settles to the bottom, clarified butter is the preferred fat to use when making a roux for future use, as it will harden when refrigerated, trapping the flour in suspension.
There are four varieties of roux: white, blond, brown, and dark brown. The different colors are a result of how long the roux is cooked; white is cooked for the shortest time, while dark brown cooks the longest. White and blond roux are the most common, used to thicken sauces, soups, and chowders. Brown and dark brown roux have more flavor, but less thickening power than white or blond roux. These roux are primarily used in Cajun and Creole dishes, most notably gumbo and jambalaya.
2. Begin making the roux by melting 1 cup of clarified butter in a saucepan over medium heat. Once the butter is hot enough that a pinch of flour sprinkled into it will slowly start to bubble, proceed to the next step.
3. Whisk 1-3/4 cups of flour into the clarified butter until a thick, rough paste forms. Whisk constantly while it bubbles over medium heat. As it cooks, the roux will become smooth and begin to thin.
4. The white stage is reached once the flour looses its raw smell, after about 5 minutes of cooking and stirring. Although slightly grainy in texture, it is much smoother than it was at the beginning. The mixture is bubbling vigorously and the color is a little paler than when the clarified butter and flour were first combined.
5. After about 20 minutes of continuous cooking and stirring, the roux will reach the blond stage. The bubbles are beginning to slow, and the aroma has taken on nuances of popcorn or toasted bread. The roux is now tan colored, very smooth, and thinner than it was at the white stage.
6. Brown roux will reach a peanut butter-brown color after approximately 35 minutes of cooking and stirring. Its aroma is more pronounced and sharper than the nutty nuances of blond roux. The roux is now thinner, and the bubbling has slowed even more.
7. Even darker than brown roux, the dark brown stage occurs after about 45 minutes of cooking, and is the color of melted milk chocolate. Its aroma will also mellow from the strong, roasted flavor of brown roux and will actually smell a little like chocolate. The roux is no longer bubbling, and is very thin.