Tuna Melt Sandwich Recipe

Drain the canned tuna thoroughly and transfer to a medium mixing bowl. Use a fork to flake the tuna into small pieces.

Add mayonnaise, Dijon mustard, minced red onion, diced celery, lemon juice, chopped parsley, salt, and black pepper. Stir until evenly combined. Taste and adjust seasoning (add more salt, pepper, or lemon juice if desired).

Cover and chill the tuna salad in the refrigerator for at least 10 minutes to let flavors meld (can be made up to 24 hours ahead).

If serving fries, start baking or frying them now according to package or your preferred recipe so they finish about the same time as the sandwiches.

Butter one side of each sourdough slice evenly with the softened butter. The buttered side will be the exterior for toasting.

Place two slices, butter-side down, on a cutting board. Divide the chilled tuna salad evenly between them and spread into an even layer, leaving a small border around the edge.

Top the tuna on each slice with 3 oz (about 3 slices or a handful if shredded) of white cheddar, then place 4–6 thin tomato slices over the cheese.

Place the remaining two bread slices on top, butter-side up, to form two sandwiches.

Heat a large nonstick or cast-iron skillet over medium-low to medium heat. Add the optional 1 tsp olive oil to the pan if desired to help browning.

When the pan is warm, place the sandwiches in the skillet. Press down gently with a spatula or place another heavy skillet on top for even contact.

Cook for 3–4 minutes on the first side, until the bottom bread is golden brown and the cheese begins to melt. Reduce heat if bread browns too quickly.

Carefully flip the sandwiches and continue cooking 3–4 minutes more, pressing again briefly, until the second side is golden and the cheese is fully melted. If needed, cover the skillet for 1–2 minutes after flipping to encourage melting.

Transfer the sandwiches to a cutting board and let rest for 1 minute, then cut each sandwich in half diagonally.

If serving salad, toss mixed greens with a pinch of salt and pepper and a light drizzle of olive oil or your preferred dressing.

Plate each tuna melt half with a portion of fries or the dressed salad. Serve immediately while hot.