Prepare Citrus Marinade by whisking together all ingredients; combine with tuna in large resealable food storage bag. Seal bag; turn to coat. Marinate in refrigerator 1 hour, turning occasionally. Drain tuna; discard marinade. Spray cold grid of grill with nonstick cooking spray. Prepare coals for direct grilling. Place tuna on grid, 4 inches from hot coals. Grill 8 to 10 minutes or until tuna flakes easily when tested with fork, turning once during grilling. Slice tuna into 1/4-inch-thick slices; set aside. Place 2 cups water in large saucepan; bring to a boil over high heat. Add beans; cook 2 minutes. Drain; rinse with cold water and drain again. Place lettuce on large serving platter and arrange tuna, beans, potatoes, tomato, egg whites and onion on lettuce; sprinkle each serving with olives. Serve with fat-free salad dressing.
Ready in 1 hour and 15 min