Boil beets, peel, chop or grate the thin strips.

Cut thin onion rings.

Scald onions in boiling water.

Chop the mushrooms, I took pickled mushrooms. If you take fresh or frozen, respectively, boiled and slice them.

Mix everything in a salad bowl. Add the optional pepper. Make a dressing from vinegar (you can take lemon juice, citric acid), water, salt, sugar and vegetable oil. Pour over the salad, let stand, lay heaped, decorate as desired with lettuce, any herbs (I had cilantro), olives. To clarify, I took a half a teaspoon of acetic acid (70% ) and 50 ml of water for refills.