Hack This French Technique to Thicken Any 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.

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. 

1. Cut 3 tablespoons of butter into ½-inch cubes and transfer to a small bowl.
2. Toss the butter with 1 teaspoon of flour, so that the pieces are amply coated and no flour remains in the bowl. 
3. 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.