School-canteen-style marinated beetroot

This is the beetroot recipe I had been looking for: the familiar dish from school canteens, summer camp and my mother's workplace cafeteria. It is wonderfully simple — beetroot, vinegar, sugar and a few spices. The first time I made it, I even left out the spices.
Adjust servings in the full version
There is no salt in this recipe!
Wash the beets and boil with spices until tender. Cool without removing from the water.
Grate the peeled beets on a coarse grater or cut into strips.
Mix sugar and vinegar in a small bowl. Wait until the sugar dissolves.
Pour vinegar and sugar over the grated beets, add vegetable oil and stir. Leave the marinade on the table for 1 hour, then put it in the refrigerator.