Peel and finely dice 1 onion. Dice the bacon. Peel, wash and slice the potatoes. Fry bacon in a large pan without fat until crispy. Fry the onion cubes briefly. Remove everything.
Heat clarified butter in bacon fat. Fry the potatoes for about 25 minutes while turning them over. Season with salt and pepper.
Cut the remaining onions into fine rings. Finely dice cucumbers. Wash apples, quarter them, remove seeds and also dice them. Mix sour cream, yoghurt and cucumber water. Season with salt, pepper and 1 pinch of sugar.
Stir in apples, onion rings and cucumber.
Rinse the maties, dab dry and cut into pieces. Fold into the yoghurt sauce. Fold the bacon mixture into the fried potatoes and heat briefly. Serve everything.