(image – Creative Commons via Cookipedia)
The Food.com Kitchen dictionary gives the following definition:
Beurre manié (French “kneaded butter”) is a dough, consisting of equal parts of soft butter and flour, used to thicken soups and sauces. By kneading the flour and butter together, the flour particles are coated in butter. When the beurre manié is whisked into a hot or warm liquid, the butter melts, releasing the flour particles without creating lumps. Beurre manié should not be confused with roux, which is also a thickener made of equal parts of butter and flour, but which is cooked before use. Because Beurre manié contains uncooked flour, liquids thickened using Beurre manié dough may have an undesirable floury or pasty taste due to the uncooked proteins in the flour.
Beurre manié serves the dual purpose of thickening as well as making your sauce nice and glossy at the same time! An easy way to blend it in is to grate it into your dish. Come autumn when I will be cooking more dishes requiring thickening this is going to be a staple of my freezer.