Boil the potatoes and beetroots into 2 separate containers. Leave them to cool. Grate the beetroots coarsely, cut the potatoes into cubes.
Peel the apples and cut them into cubes as well. In a bowl, combine the mayonnaise and cream.
In a 8″ (20 cm) diameter form, spread out 1/2 the beetroots. Smear with the sour cream and sprinkle with part of the grated cheese. Cover with 1/2 the boiled potatoes. Smear with cream and sprinkle with cheese. Cover with a 3rd layer, made of apples this time.
Smear with cream and sprinkle with cheese. Repeat the same procedure one more time (beetroots, potatoes, apples). Leave the cake in the fridge for a few hours to cool and harden. Invert it into a suitable plate. Decorate by making lines of mayonnaise, rosettes of boiled beetroots and parsley.