Tuna & Egg Salad is a simple but hearty lunch, without pretensions to the niçoise original. But it will satisfy you until dinner time.
Whisk together all the dressing ingredients and set aside.
Put all the salad ingredients EXCEPT the egg and chives into a bowl.
Toss the salad with two thirds of the dressing.
Place the egg pieces on top.
Drizzle over the rest of the dressing, sprinkle with the chives if using, and serve.