Making a Basic Roux
A roux (pronounced "roo"), isn't this impossible technique that only French trained chefs use and talk about to feel superior. It is actually just a basic, simple technique to create base for delectable sauces and gravies. Once you know the basics, you can tweak them to fit your tastes and the style of sauce you are creating.
For example, French cooking, a roux (a mix of fat and flour) is used as a natural thickener. In Cajun recipes, it's all about adding flavor. Your Thanksgiving gravy combines the two. It is simple, but takes a bit of patience. According to Jacques Pepin, the roux is only done when it is a deep, rich brown and "it smells like a roomful of toasted nuts."
Start the roux.
Heat oil in a large enameled cast-iron casserole or heavy bottomed pan or pot. This can really be any type of oil or fat including olive oil, butter (most common), bacon grease, rendered fats, canola oil, you name it. When the oil is hot, add the flour (all purpose, whole wheat, or pretty much any kind of flour) and whisk over medium low heat until it is thoroughly incorporated. The ratio is approximately 1 times fat to 1 ½ times flour. So, 1 cup butter to 1 ½ cups flour.
Whisk the roux.
Cook the roux, whisking constantly; it will turn white, blond, light brown and then dark drown after a few minutes- up to 20 for dark brown.
Finish the roux.
The roux is done when it is a deep, dark mahogany color and has a toasty aroma. This is what is called a dark brown roux, which has the most depth of flavor. For a more delicate sauce, cook the roux less to a white, blonde, or brown color.
Add liquids to the roux to make a sauce.
Once the roux is finished add your liquids (wine, liqueurs, stock, lemon juice or a mixture thereof), slowly while whisking. Then add herbs, salt and pepper to taste and cook down to desired thickness and silky smooth texture. Voila, the best sauce you ever made..