Even if you haven’t heard of a roux before, you might actually have made it on several occasions before without even knowing you made it! A roux is formed when you’re cooking equal amounts of flour and fat. This mixture is then usually used to thicken sauces, or used as a base on which you build other more complicated sauces. It can thus be said that a roux is truly a foundational ingredient upon which a multitude of other recipes are built.
The simple method of making a roux involves melting the fat over medium heat, and then adding flour, whisking until smooth. The mixture is cooked until you achieve the desired color. There are three types of roux (based on the color and the duration they were cooked), namely a white roux, a blond roux, and a brown roux.
There are various fats you can use to make your roux. Clarified butter is the preferred fat if you need a lighter-colored roux. During the process of making clarified butter, milk solids are removed. It is these milk solids that turn brown and give a nutty flavor to a roux. So, when you use clarified butter, you prevent the roux from browning too quickly.
You won’t find many chefs (if any at all) who will use margarine in their rouxs, but for home cooks, this is an affordable option. Don’t expect, however, to get the same delicious flavor as butter!
Depending on the type of dish you make, you can also opt for animal fats like schmaltz (chicken fat), beef drippings, or lard. They give a delicious flavor to brown sauces and gravies.
Another popular fat to use, is vegetable oil. It does not lend any flavor to the roux, so it is best used when you only want to thicken a sauce that already has enough flavor.
The way in which flour work as a thickener is all due to its starch content. Try to avoid high-starch flours (like cake flour) and instead opt for a flour that has more protein and less starch (like bread flour). Sometimes, chefs will brown flour separately in the oven to give it a head start on the browning process. But this browning process will actually reduce the thickening power of the flour, so keep that in mind.
The correct proportions
To make a good roux, it’s important to stick to the correct ratio – equal parts fat and flour by weight. If you use too much fat, it can make for a greasy sauce. The roux shouldn’t be too thin or runny, but firm.
Look out for future articles tackling the steps for making a perfect roux!