Tuna Sandwich Recipe

Prepare tuna

Open the cans of tuna and drain thoroughly. Transfer tuna to a medium mixing bowl and flake with a fork until mostly broken up but still slightly chunky.

Mix dressing

In a small bowl combine mayonnaise, Greek yogurt (if using), Dijon mustard, and fresh lemon juice. Whisk until smooth.

Combine filling ingredients

Add the diced celery, finely diced red onion, chopped capers (if using), and chopped parsley (if using) to the bowl with the flaked tuna. Pour the mayonnaise mixture over the tuna. Gently fold everything together with a spatula until evenly coated. Season with salt and freshly ground black pepper. Taste and adjust seasoning with more salt, pepper, or lemon juice as desired.

Prepare bread

If you prefer toasted bread, lightly butter one side of each bread slice or brush with olive oil. Heat a skillet over medium heat and toast the bread butter-side-down for 1–2 minutes until golden, then flip for 30 seconds to warm the other side. Alternatively, use a toaster and toast to your preference.

Assemble sandwiches

Place 4 slices of bread on a cutting board (buttered side down if toasted). Divide the tuna mixture evenly among them, spreading about 1/4 of the filling on each slice. Top the tuna with lettuce leaves, 2–3 tomato slices (if using), and pickles or cucumber slices (if using). Top with the remaining bread slices to form sandwiches.

Cut and serve

Using a sharp knife, cut each sandwich in half diagonally or down the middle. Serve immediately. Store any leftover tuna filling in an airtight container in the refrigerator for up to 3 days.