Boil the potatoes, peel them and cut them into cubes. Finely dice the pickles. Wash, peel, core and slice apples.
For the sauce, mix the cream yogurt, mayonnaise, tomato paste, lemon juice and water. Peel and finely dice shallots and add to the sauce. Season the sauce with salt, pepper and sugar.
Add the potatoes, cucumber and apples to the sauce, stir and let steep for an hour.
Clean the chicory and cut into strips. Wash and clean the radishes and cut into wedges. Add both to the salad and mix. Peel the eggs and cut them into sixths.
Spread the salad on plates and garnish with the eggs.