What to look out for whenmaking the classic sauce thickener.
By Margaret Eby Updated February 07, 2019
Emeril's Cajun Roux
A roux only has two ingredients—fat and flour—but can go awry in many ways. Making a good roux is one of the backbones of cajun and creole cooking, but it's also useful for all kinds of sauces, from gravy to bechamel. A roux basically takes the consistency of a liquid from thin and drippy to a classic sauce consistency that coats the back of a spoon. It's not the only way you can achieve that thicker saucey consistency. A cornstarch slurry, simple roasted flour, or an uncooked combination of flour and butter known in French cuisine as a beurre manie can be used the same way in certain cases. But for a gumbo, for example, you're going to want to make a roux. Once you've made it a couple times, you'll know what to look out for, but here are some things that can go wrong that you'll want to avoid.
You Didn't Measure the Flour and Fat
Yes, a roux is just flour and fat. Butter, oil, and drippings from meat all work as the fat. It depends on what flavor you want. But the ratio between those two things really matters for a roux, because it determines the thickening power of your end result. Too much flour and your sauce will be too thick. Too much fat and it won't be thick enough. The ratio will depend on what you want to use your roux for, but the classic roux for thickening sauces is a one-to-one ratio of flour and butter.
You're Turning Up the Heat Too Much
A roux is one of those stovetop dishes that benefits from patience. It's tempting to turn up the heat to try to nudge it along, but more often than not, that will just burn your flour and you'll have to start over again. There's no coming back from a burned roux—it'll add an acrid, unpleasant note to the dish that you just worked so hard to make.
You're Cooking It Too Much or Too Little
One of the tricky parts about roux is that it's better for different things at different stages,. A blond roux is one where the roux is just barely browned. It'll smell a little nutty, and have the consistency of wet sand. This roux is useful for bechamel or cheese sauces because it also thickens the most of any type—the more you cook a roux and the darker it gets, the less thickening power it gets. If you keep cooking the roux, it'll turn into a brown, peanut butter color, which is great for lighter gumbos and many sauces and stews. Keep pushing until the roux is a very dark brown, and that's the color you want for gumbo. That roux doesn't thicken as well as the other kinds, and it is also made best with oil or drippings, since butter can burn at high temperatures. It's a process that takes patience to get to the right stage without turning up the heat and scorching the whole thing. If you need a visual guide for what the roux will look like, try this video of Emeril Lagasse making roux.
You're Adding Hot Liquid to a Hot Roux
If you add a cold roux to a cold liquid, it won't dissolve or thicken. Likewise, adding a hot roux to a hot liquid will result in a lumpy sauce. You want to either cool the roux down and then add it to simmering liquid, or add cold liquid to the hot roux you just made. And yes—if you're worried about time and the roux process intimidates you and you want to get it over with, you can make roux ahead of time and keep it in the refrigerator or freeze.
You're Adding Your Liquid All at Once
Once you have your roux where you want it and you're adding your stock or milk or whatever else, it's important to make sure you combine them gradually. If you're thickening a sauce with rroux, add a little roux at a time and whisk until you get the consistency you're looking for. If you add it all at once, you can quickly get a sauce that's way too thick. If things get way too thick you can always add more liquid, but it'll also lessen the flavor in the dish that you're working toward.
FAQs
You're Adding Hot Liquid to a Hot Roux
Can you fix lumpy roux? ›
If it starts to clump up and look a little thick, add a little more fat. Likewise, if the roux seems thin and not thickening at all, add a little more flour. Don't go overboard. Try one tablespoon at a time until it reaches the desired consistency.
Can you fix a broken roux? ›
Another important question: Is there a fix for a roux once its broken? I only found one fix for a separated roux, which is taking pre-made cold roux from “roux in a jar” (which I don't normally use) and mixing it into the gumbo with the broken roux, and then bringing the whole thing to a boil for a few minutes.
Why is my roux not dissolving? ›
When a roux is added to a simmering pot, the flour contained in the roux forms a film, which makes it difficult to dissolve. Turning off the heat immediately lowers the temperature in the pot to about 195°F, which is an ideal temperature for the roux to dissolve easily.
Why does my roux look grainy? ›
If the roux doesn't simmer long enough, the flour in the roux will remain grainy.
How do you know if you messed up your roux? ›
You're Cooking It Too Much or Too Little
It'll smell a little nutty, and have the consistency of wet sand. This roux is useful for bechamel or cheese sauces because it also thickens the most of any type—the more you cook a roux and the darker it gets, the less thickening power it gets.
How do you fix a grainy roux? ›
Bits of flour that have not completely mixed with the fat are what make a roux lumpy. This can be fixed by cooking the fat/flour mixture for a minute or two, stirring constantly and then slowly adding your liquid. I find that an equal amount of flour and butter paired with cold or room temperature broth works best.
How to fix liquidy roux? ›
Whisk the flour into the fat until you have a smooth, thick paste. If it's too thick to whisk, add a little more fat. If it seems runny, add more flour.
Should my roux be bubbling? ›
Add the flour, salt and pepper and stir until combined. Cook, stirring frequently, for 2 minutes, until the mixture is bubbly and foamy. At this point, it should look like a thick paste. Editor's Tip: Most roux recipes instruct you to use a whisk, but I like using a rubber spatula.
What does burnt roux look like? ›
If little black specks start to appear, it's time to throw it away—even if you've been stirring for half an hour. There's no way to save a burnt roux. But you don't have to see black specks to know when something is going wrong, Parish says. "You can tell by smelling it.
Yield: Use 3 ounces roux per 4 cups liquid for a light sauce, 4 ounces for a medium-thick sauce, and 6 ounces for a thick sauce.
What is the texture of a good roux? ›
Roux (pronounced “roo”) is a simple combination of flour and fat, cooked and used to thicken and add flavor to recipes. A good roux will give a silky smooth texture and thickness to your favorite dishes. The darker the roux the more complex the end flavor is.
How do you smooth out a roux? ›
Adding hot liquid to a hot roux stops the butter from clumping and causing lumps. Adding the liquid gradually to start and mixing well between each addition. Whisking rather than stirring the sauce it cooks helps to knock out any lumps.
How do you save a curdled roux? ›
If your sauce has broken completely, there is still hope. The Kitchn recommends whisking an egg yolk with a bit of whatever liquid you are using as the sauce's base. Gradually add your broken liquid to the egg yolk mixture, one tablespoon at a time. In doing this, you're forming a fresh emulsion.
What to do if sauce is too lumpy? ›
If the sauce has just a few lumps, use a balloon whisk and whisk vigorously to break the lumps up. Use a food processor, blender or immersion blender to whizz those lumps out of sight. Return to heat and whisk until warmed through.
How to fix flour clumping in gravy? ›
Give It a Whirl in a Food Processor
Here's a high-tech lumpy gravy fix: Pour the gravy into a food processor or blender. Press liquefy or whip on a blender; for a food processor, turn it to "on" (not pulse) and use the spinning of the blades to get lumps out of gravy.
