Wash the cucumber, peel it so that some of the skin remains. Slice the cucumber. Peel onion and chop finely. Put cucumber and onion in a bowl. Add vinegar and 2 tablespoons of oil.
Season to taste with salt, pepper and sugar. Wash the chives, cut into small rolls and sprinkle over the cucumber salad. Peel, wash and slice the potatoes. Heat 4 tablespoons of oil in a pan.
Fry the potatoes for about 15 minutes at medium heat. Turn from time to time. Season with salt and pepper. In the meantime, beat the escalopes a little flatter. Season with salt and pepper. Beat the egg.
Turn the cutlets in flour, egg and breadcrumbs. Heat clarified butter in a frying pan and fry the escalopes for 3-4 minutes on each side. Arrange potatoes, schnitzel and cucumber salad on plates and serve.
Garnish with lemon.