Beurre manie 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.
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 manie 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 manie. 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._ _
