More than anything else, it's the roux that gives gumbo its particular character. Making roux is something of an art. It may take some practice to get good results. If dark specks appear, or if you smell something burning, you'll need to throw out the roux and start over. Don't try to base your gumbo on a burnt roux!
That said, let's make a nice dark Cajun roux. A Cajun roux is just flour cooked in fat until it acquires a dark color and a deep, complex, somewhat smoky flavor with nut-like overtones.
Some folks have claimed that one can make a roux in the oven or even in the microwave, omitting the fat, but the one true way is to cook the roux on the stove top in a deep, heavy skillet or Dutch oven. The catch is that it will take forty-five minutes to an hour to cook the roux at the proper temperature so that it doesn't burn, and that you will need to stir constantly, working
pretty hard the whole time. Some use a large whisk or a large spatula to keep the roux moving, but I find that a large ,long-handled wooden spoon works best.
The choice of fat does affect the taste of the gumbo. Lard and bacon fat are the traditional choices (sometimes blended together), but other animal fats, or even vegetable oil or
shortening, may be used. The choice of fat may be influenced by the kind of gumbo you are going to make -- duck fat for a duck and sausage gumbo, for example. You may decide to use vegetable fats for a seafood-only gumbo, and animal fats for your other gumbos. I myself consider either bacon drippings alone, or bacon drippings blended with vegetable shortening, excellent for making a roux. If you do use bacon drippings, you will want to strain
them carefully to remove any burnt bits before starting your roux.
Regular bleached all-purpose flour is fine for a roux. The proportions of flour to fat vary depending on how thick you want the roux to be. Approximately two parts flour to one part fat
works well for me. If I need about a cup of roux, I use a cup of flour and about half a cup of fat, perhaps increasing the quantity of fat by a tablespoon or two depending on the result I'm looking for that day.
Before we start cooking, two points of caution. First, be extra careful when making a roux, since it gets (and stays)
incredibly hot, and if you splash any on yourself, it's going to stick to you. You could get a heck of a burn if you don't watch yourself.
Second, you need to have the vegetables for your recipe already chopped and close at hand before you start cooking the roux, as well as your stock waiting on a back burner, already strained and defatted and ready to go. This is because we are going to slow the cooking of the roux by adding the vegetables (and possibly some other stuff) when it reaches the appropriate state, then after a few minutes more stirring, slowly start blending in hot
stock, a little at a time. If everything isn't ready to go in advance, you risk burning the whole mess after you've already put in an hour stirring -- so be sure to get all set up before
starting the roux.
The trick to success in making a roux is to properly regulate the
temperature of the burner. Heat the fat over medium to medium-high heat before adding the flour. Stir in the flour,
and from that point on, don't stop stirring. If the roux starts to get darker than a peanut-butter color before half an hour has passed, your heat is too high. You may still be able to rescue the batch of roux if it's not already scorched. Remove the pan from the heat, still stirring, and turn down the burner a bit. Let the heat dissipate for a while (keep stirring!) before returning the pan to the burner. It may take some experimenting before you find the right setting for your stove. If you find that you've burned the roux, you must discard it, thoroughly clean the pan and utensils, and start over.
If all goes well, the roux should change from a peanut-butter shade to a dark chocolate color about forty-five or fifty minutes into the cooking process. You should be heating your stock by now. A good gumbo requires a really dark roux, but at this point there is again some danger of burning, so prepare to add your chopped vegetables (including onions, celery and bell peppers) to slow the cooking of the roux. Keep stirring vigorously as you add the vegetables, and continue stirring as they cook. Once the
onions are transparent, start blending in your now-hot stock, little by little. You're going to keep stirring until you've blended in all of the stock. The result will be a gloriously dark, complex-flavored, authentic base for your gumbo.
