Robertson Tuna Sandwich Recipe

Prepare tuna

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

Add mayonnaise, Dijon mustard, finely chopped red onion, finely chopped celery, chopped capers, lemon juice, chopped parsley, salt, and freshly ground black pepper to the bowl with the tuna.

Fold ingredients gently until evenly combined. Taste and adjust seasoning—add up to 1 tsp additional lemon juice or 1/4 tsp more salt if desired. Refrigerate the tuna salad while you prepare the remaining components (at least 10 minutes for flavors to meld).

Preheat the oven to 400°F (200°C). Line a small baking sheet with parchment paper or foil.

Slice the tomato into 1/2-inch thick rounds. Arrange slices on the prepared baking sheet in a single layer. Brush both sides lightly with olive oil and season with 1/4 tsp salt and a pinch (about 1/8 tsp) of black pepper.

Roast in the preheated oven for 12–15 minutes, until the tomato slices have started to soften and concentrate in flavor but still hold their shape. Remove and let cool briefly on a rack (5 minutes).

If you prefer toasted bread, lightly butter one side of each bread slice. Heat a skillet over medium heat and toast the bread, buttered side down, 1–2 minutes per side until golden and warmed. Alternatively, toast in a toaster or under a broiler briefly.

Place one slice of Havarti cheese on four of the bread slices while still warm so the cheese softens slightly.

Slice the avocado halves into 1/4-inch slices and season lightly with a pinch of salt if desired.

On the four bread slices with Havarti, layer as follows: a generous portion (about 3 oz by volume) of the prepared tuna salad, 2–3 slices of roasted tomato, avocado slices (covering the tuna), shredded iceberg lettuce (about 1/4 cup per sandwich), and 3 slices of pepperoncini (or to taste) spread evenly.

Top each assembled half with the remaining bread slice, press down gently, and cut each sandwich in half on the diagonal.

Serve immediately. Leftover tuna salad will keep covered in the refrigerator for up to 2 days; assemble sandwiches just before serving to keep bread from becoming soggy.