I don't like too sharp taste of fresh onion, so I almost always, for salads it lightly pickled, whatever the bitterness left: it peeled onions cut into thin half-rings, salt, sprinkle with vinegar and oil. If you want, you can add a little sugar. While onion is marinating, do other vegetables.

The rest of the vegetables my clean. Celery and pepper cut into small pieces and put on top of the onions.

Tuna mash with a fork, cheese cut into small cubes and also add to the salad bowl.

Tomatoes, cut into large cubes and green beans, pre-cooked in boiling salted water for about 5-7 minutes and also added.

Salad pepper, stir and if necessary add salt, oil or vinegar (because of all this we added to the onion). Bon appetit!