Wash the cucumber and slice it into thin slices. Sprinkle the slices with plenty of salt and let them stand for a while (I usually prepare the cucumber before cooking starts and then when the food is ready I prepare the salad).
Peel the onion and cut into small cubes. After the cucumber has been soaked for a while, it is placed in a thin cloth and the liquid is squeezed out. Add the squeezed cucumber to the onion cubes and pour the beaker of sour cream over it. Mix everything together. Season to taste again before serving, but most of the time you don`t need more salt.