POUR 1/2 cup dressing over steak in large, shallow nonaluminum baking dish or plastic bag; turn to coat. Cover, or close bag, and marinate in refrigerator 30 minutes to 2 hours, turning occasionally.
REMOVE steak from marinade, discarding marinade. Grill or broil steak, turning once, until steak is desired doneness. Remove to plate and let stand.
TOSS arugula, onion and remaining 1/4 cup dressing in large bowl. Stir in hot Knorr® Rice Sides™ - Rice Medley. Arrange on platter, then top with sliced steak. Drizzle, if desired, with additional dressing; now it's delicious. Dig in!