One skill that really shows off a pro cook’s kitchen chops is the ability to improvise on the fly when something doesn’t turn out quite right. Smoothing out seized chocolate or clumpy custard. Coaxing broken mayo into a glossy emulsified spread. Re-solidifying oversoftened butter. Patching torn poultry skin. And of course, thickening up a too-loose pan sauce.
There’s actually a dedicated French technique for that last one called beurre manié. It’s a close relative of roux, made by mashing together equal parts butter and flour until you’ve got a paste. In many restaurant kitchens, cooks keep a tub of the stuff on hand to whisk into pan sauces by the spoonful during the final moments of cooking, because it builds body in an instant: Starch in the flour absorbs water, swells, and thickens the liquid, while the butter adds richness and prevents clumping by evenly dispersing the flour as it melts.
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Fortunately, you don’t have to be a pro cook, or have a tub of beurre manié at your disposal, to tighten up a runny pan sauce. The same effect can easily be achieved with this simpler flour-dredged butter hack.
How to Quickly Thicken Any Pan Sauce
- Cut 3 tablespoons of butter into ½-inch cubes and transfer to a small bowl.
- Toss the butter with 1 teaspoon of flour, so that the pieces are amply coated and no flour remains in the bowl.
- Whisk the pieces into any simmering sauce, a few at a time, until the mixture is luscious and cream-like, 1½ to 2 minutes.
It’s a handy, universal fix that you can throw together in minutes. In fact, I even built it into my recipe for Chicken Francese, where it lends silky richness to the lemony reduction. But if you want to plan ahead like a pro chef, you can also keep a stash of flour-coated butter in the fridge until you need it.