Uruguayan Pork “Skirt Steak” with Mustard Plum Barbecue Sauce

Ah, the redemptive powers of barbecue. What do the fajita, vacillo, and matambre have in common? All are made from thin, flat, fibrous muscles from the underbelly of the steer that overcompensate in flavor what they may lack in tenderness. Well, there’s a new budget steak on the block, and it comes not from beef, but pork. Uruguayans and Argentineans call it matambrillo, and if you see it on a menu in those countries, don’t miss it. As to exactly where it comes from, an