Capers, red onion, and fresh herbs give canned tuna and beans a light, fresh taste. Here we serve the tuna salad on a bed of greens. It also works well stuffed into a pita for a sandwich. Give it some extra kick with a pinch of crushed red pepper or cayenne. Serve with olive bread."
Combine beans, tuna, bell pepper, onion, parsley, capers, rosemary, 2 tablespoons lemon juice, and 1 tablespoon oil in a medium bowl. Season with pepper. Combine the remaining 2 tablespoons lemon juice, 1 tablespoon oil, and salt in a large bowl. Add salad greens; toss to coat. Divide the greens between 2 plates. Top each with the tuna salad.