Cut the onion in half rings, cut the apple in half, remove the middle and cut into slices. Place onion and apple together in a bowl, sprinkle with sugar and pour lemon juice, mix and let stand for 10 minutes while preparing the rest of the ingredients.
Boil green beans in salted water for several minutes, then drop in a colander and rinse with running water.
Peel the mackerel from bones and skin, cut into cubes. Add beans, apple with onions, canned corn, salt and season the salad with vegetable oil as needed.
Stir and serve.
Salted mackerel salad is quite original, but tasty, juicy and fresh. To prepare it, take apples with sourness, lemon juice can be replaced with apple cider vinegar or wine. Preparing such a salad is very simple, and in order to greatly simplify and reduce the cooking time, you can use preserves from mackerel. Such a salad will perfectly decorate any holiday table, be sure to try to cook it and maybe this particular salad will become your favorite.