Beef Skirt Steak
This lesser known cut is favored for fajitas, stir fry, Bolognese sauce, and Iberian and South American cuisines, as well as in fancy restaurants. It is flavorful with a loose texture that takes marinades very well.
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Buying: This cut is usually purchased from specialty meat stores rather than in supermarkets. The outside skirt can be found at markets that also sell direct to restaurants. Caution: Supermarkets often sell Flap Meat labeled as Skirt Steak. While these two may be interchangeable in Tex-Mex usage, the much thinner flap meat is not suitable for other uses.
Prep: Membranes are almost always present on the outside skirt and may be present on the inside skirt. They must be removed, but usually you can just pull them off with little trouble.
Cooking: This meat is generally either cooked very fast over high heat, or braised for a fairly long time. In between it will be tough. After cooking it is generally sliced thin across the grain. Caution: because this cut is so loose in texture, heat penetrates very quickly so it's easy to overcook.