Wash potatoes thoroughly and cook in boiling water for about 20 minutes. Peel garlic and chop finely. Peel and finely chop the onions. Dice cucumbers as well. Drain the potatoes, rinse with cold water and cut into bite-sized cubes.
Mix sour cream, mayonnaise, cucumber stock, diced onion and garlic, season with salt, pepper and sugar. Wash the chives, shake dry and cut into fine rolls. Mix potatoes, cucumber and chives with the salad dressing in a bowl. Cover the salad and chill.
Fry the bacon in a pan without fat until crispy. Take out and let drain on kitchen paper. Grate cheese. Coarsely crumble the bacon and sprinkle the cheese over the salad.