Lelehan Tuna Terbaik

Bahan-bahan (8 porsi)

• 16 ounces tuna fish, (drained)
• 1/4 cup mayones
• 1/4 cup celery, (finely chopped)
• 1/4 cup red onion, (finely chopped)
• 1 tablespoon dijon mustar
• 2 tablespoons parsley, (chopped)
• garam dan merica, (secukupnya)
• 16 slices roti
• 8 slices keju cheddar, (bisa lebih jika ingin lapisan di bagian bawah)
• tomato, (sliced)
• 1/4 cup butter, (softened)