What is a roux sauce in cooking?

A roux is a mixture of flour and fat or oils that is used to thicken sauces, like for your child’s favorite mac and cheese or your fall chili recipe. Learn how to make a roux to use as a simple base for your favorite sauces and dishes.

What is a roux? 

A roux is a thickening agent made by heating equal parts starch and either fat or oil in a pan until a smooth paste is formed. Typically, vegetable oil, canola oil, lard or butter can be combined with a starch, like all-purpose white or wheat flour, to serve as a base for your saucy dish. During cooking, the flour absorbs moisture, leading to a sauce with a smooth consistency.

A roux can range from light to dark in color and darkens the longer it cooks. Typically, light colored roux is used to thicken dishes like soup or chowder, and is heated for a few minutes. Darker colored roux sauce is cooked longer and boasts a deeper flavor, which is ideal for dishes like seafood gumbo or gravy.

Roux pronunciation: the meaning behind the word

Pronounced with a silent “x,” “rü” is a French cooking term and was originally used to thicken sauces, like béchamel and other native recipes in the 17th century. With a direct translation to “redhead” in French, roux sauce usually has a light brown shade and darkens the longer it cooks.

Although originally used for French sauces, roux has gained popularity in Cajun and Japanese recipes and serves as a hefty base for gumbo and curry dishes, as well as creamy cheese sauces.

How to make a roux for cheese sauce

A roux for cheese sauce can be made by heating just two ingredients for a thick, creamy base—butter and flour. Whisking frequently, combine and heat the butter and flour in a pan, but be mindful of the color and avoid overcooking it into a darker hue.

When your roux has cooled off and has a smooth, thick texture, combine it with milk and then your favorite cheeses for a simple, yet filling, mac and cheese sauce.

Learn more cooking tips for your next roux recipe and other meals.

Shop Whirlpool^® Cooktops for making roux

Whirlpool brand offers a wide variety of gas and electric cooktops and ranges to help you with your next roux recipe.

How to make a roux without flour

Roux can be made by substituting cornstarch or arrowroot powder for flour. First, mix the cornstarch or powder with water until it reaches a thick consistency. Then, combine this mixture with your oil or butter and heat it in a saucepan. Whisk for a few minutes until your roux sauce is smooth, absent of lumps and has a light color.

Is a roux necessary for making cheese sauce?

While cheese sauce can be made without roux, adding roux to your recipe is helpful for achieving a rich sauce that coats the pasta. When flour is added to the simmering fat, the starch granules are activated, and this process thickens the sauce. Without roux,  a cheese sauce can become thin and runny.

How does the color of roux affect taste?

The color of roux ranges from light to dark and is determined based on how long the flour and butter are heated. A lighter roux is ideal for white sauces, like béchamel, and should be cooked for about two to three minutes to achieve this color and mild, less robust  flavor. A darker roux is heated longer for a dark shade of brown and rich, gravy-like flavor.

Explore Whirlpool^® Ranges

Whether you’re whipping up a light roux for cheese sauce or cooking a dark roux for your favorite Cajun specialty, Whirlpool brand has a wide array of ranges with convenient features on select models, like Edge-to-Edge Cast-Iron Grates and SpeedHeat™ Burners, to help you keep mealtime under control.