Step 1

In a bowl, whisk together all of the ingredients. Season with salt and pepper. Set aside.

Step 2

Place the potatoes in a pot. Cover with cold water and season with salt. Bring to a boil and simmer for 12 minutes or until just tender. Drain and let cool on a large plate.

Step 3

Meanwhile, in a pot of salted boiling water, cook the green beans for 2 minutes. With a slotted spoon, remove the green beans and plunge into ice water. Place a steaming basket in the pot. Place the eggs in the basket. Cover and cook for 9 minutes. Plunge the eggs in the ice water to immediately stop the cooking. Drain. Peel the eggs. Set the eggs and green beans aside.

Step 4

In a small bowl, combine the water, vinegar and sliced onion. Let marinate for 2 minutes. Drain.

Step 5

In shallow dishes, arrange the lettuce, bell peppers, cucumber, tomatoes, potatoes, green beans and onion. Top with the eggs cut in half, tuna and olives. Drizzle with the dressing.