Boil the potatoes and green beans until tender, then drain and cool.

Hard-boil the eggs, peel, and quarter them.

In a large bowl, combine the tuna, potatoes, green beans, cherry tomatoes, olives, and salad greens.

In a small bowl, whisk together olive oil, red wine vinegar, Dijon mustard, salt, and pepper.

Drizzle the dressing over the salad and toss gently to combine.

Top with the quartered eggs before serving.