Tuna-pesto melts on rye with romaine salad with candied walnuts and Grapefruit Recipe

Ingredients

• 2 cooked tuna fillets, broken into 2.5-cm pieces
• 60g prepared basil pesto
• 2 tbsp jarred roasted red peppers, diced
• 2 to 3 tbsp mayonnaise
• 1 tbsp grated Parmesan
• Salt
• freshly ground black pepper
• 4 thick slices rye bread
• 8 slices Swiss cheese
• 3 tbsp olive oil
• 3 tbsp seasoned rice vinegar
• 2 tsp Dijon mustard
• 400-600g chopped Romaine lettuce leaves
• 200g ruby red grapefruit segments
• 30g candied walnuts, pecans or peanuts