Tuna-Pesto Melts on Rye with Romaine Salad with Candied Walnuts and Grapefruit

For the tuna melts:

• 2 cooked tuna fillets, broken into 1-inch pieces (about 2 cups)
• 1/4 cup prepared basil pesto
• 2 tablespoons jarred roasted red peppers, diced
• 2 to 3 tablespoons mayonnaise
• 1 tablespoon grated Parmesan
• Salt and freshly ground black pepper
• 4 thick slices rye bread
• 8 slices Swiss cheese

For the Romaine salad:

• 3 tablespoons olive oil
• 3 tablespoons seasoned rice vinegar
• 2 teaspoons Dijon mustard
• 4 to 6 cups chopped Romaine lettuce leaves
• 1 cup ruby red grapefruit segments
• 1/3 cup candied walnuts, pecans or peanuts