Beurre manié is one of the best ways to thicken a sauce or a soup, period. This fancy-sounding mixture—it means kneaded butter in French—is incredibly simple to make and equally easy to use. Just rub enough flour into softened butter to make a thick paste; then whisk in little bits of the paste to finish a pan sauce for, say, shrimp scampi or a roast turkey, or to enrich a seafood chowder. As the butter melts, it separates and evenly disperses the flour particles, which swell and thicken the liquid. The result: a lustrous, velvety texture with nary a clump. Once a technique that was employed by professional and home cooks, unfortunately, this smart kitchen trick is rarely seen anymore. We think it's time to revive it.
How to Do It:Simply mix equal parts of softened butter and flour together in a small bowl, and use your fingers or a fork to form a smooth paste. Then roll teaspoon-size amounts of the paste into balls. (You can also make large amounts of beurre manié in a food processor and store the balls in the freezer, bringing them to room temperature before use.)
When simmering a sauce, whisk in one ball at a time as needed. Allow the mixture to return to a boil, and cook for at east 1 minute to thicken. If your sauce is not as thick as you'd like, add a bit more beurre manié. The butter-coated flour particles will melt and quickly thicken the sauce as it simmers, and the additional butter will add a sleek luster, similar to the effect of mounting a sauce with cold butter.