How to Make a Roux for Gravy, Sauces, and Soups

A roux is a cooked mixture of flour and fat used to thicken gravy, sauces, soups, and stews. To make one, melt fat over medium to medium-low heat, whisk in an equal amount of plain flour, and cook until the mixture reaches the color and aroma you want. Then gradually whisk in stock, milk, or pan juices.

The basic working ratio is 1 part fat to 1 part flour by weight. In a home kitchen, equal spoonfuls of butter and flour are a practical approximation, though weighing gives more consistent results. Cook the flour long enough to remove its raw taste, but stop before the roux becomes darker than the sauce you want.

The basic roux method

For a starting batch, use:

4 tablespoons butter, bacon fat, pan drippings, or neutral oil
4 tablespoons plain all-purpose flour
About 3 to 4 cups stock, milk, or other cooking liquid, added gradually
Salt and other seasonings, added after the liquid is incorporated

This makes a useful base for gravy or a sauce. The final thickness depends on the amount and type of liquid, how long the sauce simmers, and how much roux you use.

1. Heat the fat

Put the fat in a saucepan or skillet over medium to medium-low heat. Butter should melt and foam lightly, but it should not brown unless you specifically want that flavor. If using pan drippings, allow very hot drippings to settle slightly before adding flour; flour can scorch in fat that is aggressively hot.

2. Whisk in the flour

Add the flour all at once and whisk until no dry pockets remain. The mixture should form a smooth, moist paste. It should not look dusty, crumbly, or like a pool of grease. If it seems dry, add a little more fat. If it is loose and oily, whisk in a small amount of flour.

3. Cook to the desired color

Keep the roux moving with a whisk or wooden spoon, scraping the bottom and corners of the pan. The color and smell tell you when it is ready.

Roux	Appearance and timing	Best uses
White	Pale and smooth; usually a few minutes	Béchamel, cheese sauce, cream soup, light gravy
Blond	Light golden, with a mild nutty smell; often about 5 to 7 minutes	Velouté, chicken gravy, lighter pan sauces
Brown	Deep golden to brown, with a pronounced toasted aroma; longer cooking	Rich gravies, stews, gumbo, dark sauces

The longer a roux cooks, the more flavor and color it develops. It also loses some of its thickening power as the flour toasts. That means a brown roux may require more roux than a white roux to thicken the same amount of liquid.

A white roux still needs to cook. Two or three minutes is often enough to soften the raw flour flavor without adding noticeable color. Do not use color alone as the test: a pale roux that still smells strongly of raw flour needs more time.

How to add the liquid without lumps

The easiest approach is to add cool or room-temperature liquid to a hot roux in small additions. Begin with a splash, whisking until the mixture becomes smooth and thick. Add another small amount, whisk again, and continue until the roux has loosened. You can then pour in the remaining liquid in a steadier stream while whisking.

For a smooth sauce:

Take the pan off the heat briefly if the roux is very hot.
Add a small splash of stock, milk, or pan juices.
Whisk firmly, especially around the edges of the pan.
Add more liquid only after the previous addition is smooth.
Return the pan to medium heat and bring the sauce to a gentle simmer.
Cook until thickened, stirring regularly.

If you have hot liquid ready, let the roux cool slightly before adding it. The important practical rule is to avoid combining a very hot roux with a large amount of very hot liquid all at once.

Pan juices can make excellent gravy, but they vary in salt and fat. If the drippings are mostly fat, use them as the fat portion of the roux and add flour as needed. If they contain a lot of concentrated juices, account for that liquid when adding stock. Taste for salt only after the gravy has reduced and thickened.

Adjusting the roux ratio

Equal parts fat and flour are a dependable starting point, but the roux should look right before liquid is added. A common professional formula is slightly more flour than fat by weight—roughly 60 percent flour to 40 percent fat. At home, the difference between that and a simple 1:1 ratio is usually less important than the consistency of the paste.

Use a little more flour for a thicker, more substantial sauce. Use a little more fat if the mixture is stiff or difficult to whisk. For a delicate sauce, start with less roux and add more only if needed; it is easier to thicken a sauce further than to correct one that has become heavy.

Remember that a roux thickens more as the sauce simmers and cools. Stop cooking when the sauce is slightly looser than your final target.

White roux vs. blond roux vs. brown roux

A white roux preserves the light color of milk, cream, and pale stock. It has the most thickening power and is the usual choice for béchamel, sausage gravy, and many creamy soups.

A blond roux adds a gentle toasted flavor while keeping the sauce relatively light. It works well with chicken stock, seafood stock, and lighter gravies.

A brown roux contributes a deeper color and roasted flavor. It is useful when that flavor is part of the dish, not simply when you need thickening. Keep the heat moderate and stir constantly; dark roux can go from properly toasted to scorched quickly.

Common roux problems

The sauce is lumpy

The liquid was probably added too quickly, or the first additions were not whisked smooth. Continue whisking over moderate heat. If necessary, strain the sauce through a fine sieve or blend it carefully, then return it to the pan.

The sauce tastes like raw flour

The roux needed more cooking, or the finished sauce did not simmer long enough. Next time, cook a white roux for a few minutes before adding liquid, then simmer the sauce until the flour flavor disappears.

The roux is greasy

There is too much fat for the flour, or the flour was not fully incorporated. Whisk in a small amount of flour while the pan is over low heat, then cook it briefly before adding liquid.

The gravy is too thin

Let it simmer a little longer first. If it still needs help, make a small additional roux in another pan and whisk the finished gravy into it gradually. Adding dry flour directly to hot gravy usually creates lumps and a floury taste.

The roux burned

Discard it and start again. A scorched roux will carry a bitter flavor into the entire sauce. Use lower heat and keep stirring, especially as the roux darkens.

Can pancake mix replace flour in a roux?

Pancake mix is not a dependable substitute for plain flour. It may contain leaveners, sugar, salt, powdered milk, or other ingredients that can change the flavor, color, texture, and thickness of the sauce. Some mixes are also formulated to absorb liquid differently from all-purpose flour.

For a predictable roux, use plain all-purpose flour unless a recipe specifies another flour. If you are out of flour, a cornstarch slurry or another thickening method is usually more reliable than guessing with pancake mix.

A simple rule to remember

Melt the fat, whisk in the flour, cook out the raw taste, and add liquid gradually. Choose the lightest roux that gives you the flavor and color you want. For most everyday gravy and sauce, an equal-parts butter-and-flour roux is the place to begin.