Buerre manie (“kneaded butter”) is a method of using starch to thicken liquids without risking clumps.  Starch (traditionally wheat flour) is pressed into clumps of butter (traditionally in a 1 to 1 ratio) before being added to the pot or pan.  The butter fat coats the flour granules and holds them apart, releasing them as the butter melts & preventing them from sticking together in clumps.  The effect is similar to a roux, but doesn’t involve toasting the flour before using it to thicken.

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