Potato-bean-tuna salad

Here's a salad recipe that I could think of meeting both in the Finnish as well as in the Northern Italian kitchen. It is served warm and it contains only a little greenery.

Ingredients:
potatoes
tuna fish in water
chives
beans (preferably of different colours)
egg(s)
white vinegar
olive oil
salt
pepper

Preparation:
Peel the potatoes and cut them into cubes. Cook them in water. Cook also the eggs in water. Rinse the chives and cut them in shorter pieces and put them on a plate. Place the readily prepared beans on the plate too. Remove the water of the tuna fish and add the tuna in the form of flakes on the plate. Add the potato cubes. Pour a little vinegar, olive oil, salt and pepper on the salad and mix. Slice the egg into a few pieces and dispose them on the plate.