To prepare dressing, place first 9 ingredients in a food processor or blender; process 1 minute or until smooth. Cover and chill.
To prepare salad, place potatoes in a saucepan; cover with water. Bring to a boil. Reduce heat; simmer 10 minutes or until tender. Drain and rinse with cold water. Drain and cut potatoes in half. Set aside.
Cook beans in boiling water 3 minutes or until crisp-tender. Drain and rinse with cold water; drain. Set aside.
Prepare grill or grill pan.
Sprinkle fish with salt and pepper. Place fish on a grill rack or grill pan coated with cooking spray; cook 4 minutes on each side or until fish flakes easily when tested with a fork. Break fish into large chunks. Arrange fish, beans, and onion in the center of a large serving platter; arrange potatoes, tomatoes, and egg around fish mixture. Sprinkle with parsley, capers, and olives. Drizzle with dressing.