"Combine beans, tuna, bell pepper, onion, parsley, capers, rosemary, ¼ cup lemon juice and 2 tablespoons oil in a medium bowl. Season with pepper. Combine the remaining ¼ cup lemon juice, 2 tablespoons oil and salt in a large bowl. Add salad greens; toss to coat. Divide the greens among 4 plates. Top each with the tuna salad."