Ingredients:

  • 2 cans (5 oz / 142g each) tuna in water, well-drained
  • 1/3 cup (80g) mayonnaise
  • 1 tbsp (15ml) lemon juice, freshly squeezed
  • 2 tbsp (30g) celery, finely diced
  • 2 tbsp (30g) red onion, minced
  • 1 tbsp (15g) fresh parsley, chopped
  • ½ tsp (3g) salt
  • ¼ tsp (1g) black pepper
  • 12 slices (approx. 340g) sourdough or sturdy white bread
  • 1 ½ cups (170g) sharp cheddar cheese, shredded
  • ½ cup (56g) mozzarella cheese, shredded
  • 2 tbsp (30g) melted butter

Instructions:

  1. In a medium bowl, fold together the drained tuna, mayonnaise, lemon juice, diced celery, red onion, and parsley. Stir in the salt and pepper until the mixture is well-combined and velvety.
  2. Preheat oven to 400°F (200°C). Use a 2-inch circular cutter to punch out two rounds from each slice of bread (24 rounds total). Arrange them on a parchment-lined baking sheet.
  3. Lightly brush the tops of the bread rounds with melted butter.
  4. Place a pinch of shredded cheddar on each bread round to create a moisture barrier. Spoon 1 tablespoon of the tuna mixture onto the cheese.
  5. Top each bite with a generous pinch of mozzarella and the remaining shredded cheddar.
  6. Bake on the center rack for 10–12 minutes until the cheese is bubbling and mahogany-colored and the bread edges are toasted and rigid.