1/2 teaspoon kosher salt
1/2 teaspoon brown sugar
1/2 teaspoon ground ancho chile powder
1/4 teaspoon ground cumin
Dash of freshly ground black pepper
1 (1-pound) flank steak, trimmed
2 teaspoons olive oil
Combine first 5 ingredients in a small bowl; rub evenly over both sides of steak.
Heat oil in a large skillet over medium-high heat. Add steak; cook 3 minutes on each side or until desired degree of doneness. Let stand 5 minutes; cut steak diagonally across grain into thin slices.