Begin by selecting your fat of choice. Traditionally, butter is a popular option and clarified butter is best, as it imparts a rich and creamy flavor. However, you can also use other fats like vegetable oil or bacon grease (these are generally used for dishes such as Gumbo or Jambalaya and are essential in Cajun Cooking. These are affectionately known as liquid napalm as the present a major potential of burns when preparing).

Rule of Thumb for thickening with a Roux:

For medium thickness, 1 lb roux to 1 gallon of liquid (8 oz butter / 8 oz flour)

For every 4 cups of liquid (quart), 4 ounces of roux (2 oz butter / 2 oz flour).

Place a saucepan over medium heat and add the chosen fat. Allow it to melt completely and come to a gentle sizzle. It's important to heat the fat gradually to avoid scorching.

Once the fat has melted, add the flour all at once while whisking continuously. Pre-sifted flour works best, but isn't mandatory.  A whisk is essential (or you can use a wooden spoon) to ensure the flour incorporates smoothly into the fat, preventing any lumps from forming. The ratio of fat to flour is equal parts by weight, but you can adjust it based on your desired thickness.

Continue whisking the mixture over medium heat, ensuring that the flour cooks evenly.  You are looking for a “wet sand” appearance. This process, known as "cooking out the rawness," and it helps develop the flavor and removes any unpleasant floury taste. The color of the roux will gradually change as it cooks, ranging from pale yellow to blonde and finally a deep, nutty brown.

Each stage of roux has a different aroma.  While a pale roux provides the smell of butter cookies, blonde and brown roux provide the smells of popcorn and a nutty flavor respectively.

The cooking time for the roux can vary depending on the desired color and flavor. A light-colored roux, often used in white sauces, requires only a few minutes of cooking. On the other hand, a dark roux, used in dishes like gumbo, may require up to 20 minutes of patient stirring and monitoring to achieve its deep, caramelized flavor.

Once the roux reaches your desired color, remove it from the heat and let it cool  before incorporating it into your recipe. Remember that the roux will continue to cook and thicken the sauce as it simmers.

Always add cold to hot or hot to cold.  Never add a hot roux to a hot liquid or it will cook into lumps.

Now, armed with the perfect roux, you can add it to your soups, stews, gravies, or sauces to create a velvety texture and enhance the flavor profile of your dishes. Just remember to adjust the cooking time accordingly, as the roux will affect the overall cooking process.

A Roux can be prepared in advance and refrigerated for later use and may be stored at room temperature if the base is oil, butter based can be kept in the refrigerator for 6 months and frozen for up to a year.  Simply add it to a pan over low heat to warm, or defrost in microwave and use as fresh! Remember to let it cool before you incorporate it into your sauce or soup.

Remember, cold to hot, hot to cold, never the same temp!

Add roux to your liquid with a balloon whisk for even distribution.