Ingredients
4 tablespoons white wine vinegar
2 tablespoons unsweetened cocoa powder
2 tablespoons firmly packed brown sugar
2 tablespoons olive oil
1 tablespoon ground cumin
2 teaspoons ancho chili powder
1 1/2 teaspoons salt
Pinch ground black pepper
2 pounds flank steak
Preparation
In a large resealable plastic bag, combine vinegar, cocoa, brown sugar, olive oil, cumin, chili powder, salt, and pepper. Add flank steak; seal bag, and refrigerate for 1 to 2 hours or overnight.
Remove steak from marinade and discard marinade. Place steak on the grill and cook for 6 minutes on each side for a medium-rare. When cooked to desired doneness, move from the grill to a cutting board, and let rest for 10 minutes. Cut steak across the grain into thin strips.
