Roux (pronounced somewhat like the English word “rue”)  is a mixture of flour and fat which is typically butter, margarine, or vegetable oil and is used as a thickening agent in sauces, stews, gravies, soups, and other culinary preparations. In some cases the fat used in making a roux can be in the form of lard or bacon fat.  There are also some non-fat non-traditional versions where a roux is made from browning flour in the oven. This form of roux omits the fat, but also lacks in flavor and thickening power. Roux is another one of those basic preparations that is required for many Cajun dishes such as gumbos, etouffees, sauce piquant, and other thickened soups too.

The classic roux has it’s origins in French cuisine and can range from a very light roux which is cooked for a short period of time to a very dark roux which is cooked for a very long time period. Two things happen to a roux as it continues to cook on the stove top; 1. the intensity of the flavor increases and strengthens, and 2. the thickening power decreases. For preparations where thickening is more of a requirement than flavor then a lighter roux is utilized, and for preparations where flavor and color is more important a darker roux is required. The varying stages of roux can be described as starting with the least cooked light roux, and then moving to the medium-light roux, medium roux, medium dark roux, dark roux, and very dark roux. To recap, the longer a roux cooks the darker it gets with a stronger flavor profile and the thickening power is reduced. In classic French preparations a roux is the basis preparation for velouté, béchamel, and espagnole sauce preparations.

I found a very nice progression of roux images on Flikr by plakidas who demonstrated making a gumbo in the photostream.

Ingredients and proportions 

A typical roux consists of 1 part flour to 1 part fat either by weight or volume, for example, 1 cup flour and 1 cup butter. However on occasion I find myself adding a bit more flour than fat, but this still is a good starting point for making any roux.

Preparation

Start with heating the fat in a large sauce pan or in a large cast iron skillet as the Cajun traditional method and put it over a medium high heat on the stove top. Once the fat is hot gradually incorporate the flour and use a wire whip to get it into the fat. Once the flour is dissolved and smoothed into the fat switch to a wooden spoon and stir constantly to keep the roux from burning. As you cook the roux longer it will get darker and you will smell a nutty aroma the darker it gets. Making a very dark roux can take up to 30-45 minutes to make depending on the amount you have and how dark you want it, stirring constantly requires patience, attention to detail and switching arms often. Ambidexterity comes in handy with a dark roux.

Notes

• Typically the amount of light roux needed to thicken a velouté or béchamel sauce is 3/4 pound roux per gallon of liquid stock or dairy product. And the amount needed to thicken a cream based soup is about 1/2 pound roux per gallon of liquid. Of course these proportions are somewhat of my personal taste, and it depends on the ultimate preparation, but for the most part sauces are thicker than soups.
• When adding a roux to a liquid be sure that the roux has cooled and that the liquid is not boiling, incorporating these two very hot items at once will result in a lot of splattering similar to a volcano spewing hot molten lava. Not a perty sight or safe procedure in any kitchen. And a wire whisk comes in handy again for incorporating the roux to the liquid.
• Roux can be made ahead and stored for up to a week. Make sure it is covered well and refrigerated if it was made with butter or margarine, a roux prepared with vegetable oils or lard can be stored at room temperature if covered well.
• Darker roux’s are typically used for darker sauces such as the espagnole which is a brown sauce, gumbos, and sauce piquant.

Variations

• I mentioned earlier that some folks prepare a non-fat roux and it is typically done in the oven, but some do prepare it on the stove top too. For the oven method take your flour and spread it out on a cookie sheet or sheet pan and bake it in a 375° F oven, and about every 10-15 minutes open the oven and stir the flour well with a spoon or metal spatula. Do this until you have the desired “toasted” flour you require. For the stove top method place the flour in the sauce pan or cast iron skillet over a medium high heat and stir the flour until the desired color is achieved. While these two methods offer lower fat options the flavor profile is missing and typically serves only as a thickening agent for the preparation.
• In some soup and sauce recipes the light roux is made with the addition of seasonings and vegetable ingredients. For example, my typical etoufee recipe starts with sauteing the onions, celery, bell peppers (Trinity) and garlic in fat until soft and then adding the flour to make a roux-like paste that includes the vegetables. This method also absorbes the liquid from the vegetables and becomes the thickening agent for the sauce.

This is the etoufee sauce recipe from the Hyatt Regency Hotel in New Orleans from 1984 that I used to prepare on a weekly basis while holding the Saucier position. The yield on this recipe was enough to prepare about 120 – 8 ounce portions of sauce. When I prepare an etoufee at home it is something that I just throw together and have yet to write up a home version of this recipe, the next time I will document it for the scaled back version.

Etoufee Sauce – Hyatt Regency Hotel New Orleans

Ingredients

2          each     Tomatoes diced (#10 cans)

1          lb         Margarine

8          oz         Garlic, minced

6          lb         Onions, small dice (1/3 full sheet pan 4” tall)

6          lb         Celery, small dice (1/3 full sheet pan 4” tall)

6          lb         Bell pepper, small dice (1/3 full sheet pan 4” tall)

1          lb         Flour

4          gal        Brown sauce

4          bunch   Green onions, diced

2          bunch   Parsley, chopped

2          cups     Red wine

2          cups     White wine

1          Tbsp    Thyme

1          Pinch    Oregano

4          each     Bay leaves

Procedure

1.  Melt margarine and sauté garlic with ½ the green onions and ½ the parsley.

2. Add the onion, celery and bell pepper and sauté until soft

3. Add the flour to absorb the liquid.

4. Add the herbs and cook another 5 minutes.

5. Add the two wines and the diced tomatoes and stir well.

6. Add the brown sauce and stir well, and bring to a boil and then simmer for 15-20 minutes.

7. Add the remaining green onions and parsley for garnish.

  Add shrimp or crawfish depending on the menu item being served.