Try THiS --> Tuna Nicoise <-- summer sandwich

Ingredients
Nicoise:
1 (6-ounce) can white chunk tuna, drained
2 eggs, hard-boiled, halved
1 tablespoon capers
10 nicoise olives, pitted
3 tablespoons mayonnaise
1 teaspoon fine herbs
Salt and freshly ground black pepper
Sandwich:
2 potato buns
2 Bibb lettuce leaves
6 slices Roma tomato
1/4 red onion , thinly sliced in rings
For Nicoise:
Directions
Combine all nicoise ingredients in a medium bowl. Mix thoroughly.

For Sandwich

Open potato buns and place 1 lettuce leaf on the bottom half of each bun. Divide nicoise mixture between the 2 sandwiches. Top each with 3 tomato slices and red onion rings.