This method takes longer than traditional or microwave roux, but needs less attention. Though you need to stir it every 20 minutes, you don't have to worry about it burning or cooking too fast. It took 2 1/2 hours at 350°F for this roux to reach a dark, or chocolate, color (see photo).
If you're going to be spending time in the kitchen anyway, you could easily make a large amount of roux using this method. Just set the timer for 20 minutes and stir each time the timer rings, until your roux is the desired color.
A darker roux (one that has been cooked longer) will have more flavor but will have less thickening power; this is because flour loses its ability to thicken the longer it is cooked.
The roux seems to be cooking very fast or getting very dark, turn the heat down. Above all, stir almost constantly — at least every 15 seconds; with each stir, the roux gets just a bit browner. I like to use a flat metal spatula (like a pancake turner) as it covers more surface area than a spoon.
When the roux reaches the desired color, you may proceed with a recipe, adding the holy trinity of onion, celery, and bell pepper, and whatever main ingredient you are using, plus seasonings and water.
Rouxmor (or Roux Humor)
As they do with almost every aspect of their lives, Cajuns have many jokes about cooking--there are two that go along with nearly every discussion of roux. The question is posed: "How long does it take to make a roux?" And the answer if one of two:
1. The amount of time it takes to drink a six-pack of beer, or
2. The amount of time it takes to brew and drink a pot of coffee.
I'd like to share an interview with Chef Kevin Belton of New Orleans School of Cooking, that was in the cookbook, Soul, and Spice, by Heidi Cusick-Dickerson. Kevin "has fond memories of his mother making roux." He recalls:
"My mama made her roux at a high temperature, so it didn't take as long. But she couldn't leave it, no matter if the doorbell rang or anything. That meant I had a good fifteen minutes to jump off the bed and she couldn't catch me because she was making the roux. I learned to judge the time by the aroma coming from that roux. Just as it begins to brown, the flour has a nutty fragrance that means it's almost done. I could smell it changing and I knew when to get off the bed.¹
- 2 cups all-purpose flour
- 2 cups oil
- Preheat oven to 350°F.
- Whisk the flour and oil in a cast iron skillet or pot until thoroughly smooth and lump free.
- Place the roux in the oven for approximately 2 to 2 1/2 hours, stirring it thoroughly every 20 minutes until the roux is the desired color: light, medium, or dark — aka blonde, peanut butter or chocolate. (It took about 2 1/2 hours for the roux to reach the chocolate color you see in the photo.)
Make Ahead Roux
If you are making the roux ahead to keep as needed, transfer it to a large glass or plastic bowl to stop the cooking process, stirring occasionally as it cools down. Roux can be kept in the refrigerator for two months, or in the freezer for six months.
If freezing the roux, place 1 tablespoon of the roux in each section of an ice cube tray and, when firm, transfer to a freezer bag. When a recipe calls for 1/2 cup roux, pop out 8 cubes (8 tablespoons, or 1/2 cup). You may also use a cube or two at a time if your stew, soup or sauce needs a bit of thickening.
3 cups oil + 3 cups flour = 3 2/3 cups roux
1 cup oil + 1 cup flour = 1 cup plus 3 tablespoons roux
If a recipe calls for making a roux with 1/2 cup oil and 1/2 cup flour, use 1/2 cup of prepared roux, or a quantity of prepared roux equivalent to the amount of flour called for in the recipe.
To thicken 6 to 8 cups of liquid for a gumbo, soup or another dish, use 1 cup prepared roux, or start with 1 cup flour and 1 cup fat.
What to Look for When Cooking Roux
After a few minutes the roux is likely to become foamy and remain so for several minutes. After about 10 minutes the roux will begin to turn dark and will develop a nutlike fragrance. After about 20 minutes the roux will start to cook faster and must be watched more carefully so it doesn't burn. Lower the heat if necessary--a burned roux is only fit for the garbage.
If the roux starts to smoke, lower the heat or turn the off for a bit to allow the roux to cool down. If the oil gets hotter than the point at which it starts to smoke, it may negatively affect the taste.