Stir the soup, oil, vinegar, soy sauce, ginger and garlic powder in a medium bowl. Reserve 1/2 cup soup mixture for salad.
Lightly oil the grill rack and heat the grill to medium. Grill the chicken for 15 minutes or until it's cooked through, turning and brushing often with the 1/2 cup remaining soup mixture. Discard any remaining soup mixture. Cut the chicken into thin strips.
Arrange the salad greens, oranges and green onions on a serving platter. Top with the chicken and drizzle with the remaining soup mixture.
Ingredient Note: Slivered almonds or crunchy Chinese noodles make a nice topping for this salad.