PreparationMake dressing: Whisk together Worcestershire sauce, oil, thyme, and salt. Grill onions and steak: Prepare a gas grill for direct-heat cooking over moderately high heat. Toss onions with 2 tablespoons oil, 1/4 teaspoon salt, and 1/4 teaspoon pepper. Cut steak into 4 pieces and sprinkle with remaining 1/2 teaspoon salt and 1/4 teaspoon pepper. Oil grill rack, then grill steak, covered, turning over once, 6 to 10 minutes total for medium-rare. Transfer to a cutting board and let stand while onions cook. Grill onions in grill basket, covered, stirring occasionally, until charred and tender, 6 to 8 minutes. Assemble salad: Toss arugula and onions with some of dressing. Slice steak and serve, drizzled with dressing to taste, with arugula salad. Cooks' note:Steak and onions can be cooked in an oiled well-seasoned large (2-burner) ridged grill pan. Grill steak as above but for 9 to 11 minutes, and grill onions in pan (not in grill basket), uncovered.
PreparationMake dressing: Whisk together Worcestershire sauce, oil, thyme, and salt. Grill onions and steak: Prepare a gas grill for direct-heat cooking over moderately high heat. Toss onions with 2 tablespoons oil, 1/4 teaspoon salt, and 1/4 teaspoon pepper. Cut steak into 4 pieces and sprinkle with remaining 1/2 teaspoon salt and 1/4 teaspoon pepper. Oil grill rack, then grill steak, covered, turning over once, 6 to 10 minutes total for medium-rare. Transfer to a cutting board and let stand while onions cook. Grill onions in grill basket, covered, stirring occasionally, until charred and tender, 6 to 8 minutes. Assemble salad: Toss arugula and onions with some of dressing. Slice steak and serve, drizzled with dressing to taste, with arugula salad. Cooks' note:Steak and onions can be cooked in an oiled well-seasoned large (2-burner) ridged grill pan. Grill steak as above but for 9 to 11 minutes, and grill onions in pan (not in grill basket), uncovered.