Wash the potatoes and cook in boiling water for 15-20 minutes. Drain, rinse with cold water, peel and let cool. Clean, wash and cut the beans into bite-sized pieces. Cook in boiling salted water for about 15 minutes. Peel onions and cut into rings.
Cut potatoes into slices. Finely dice bacon, leave it crispy in a small pot and take it out. Bring vinegar to the boil in the bacon. Steam onion rings for about 1 minute. Season with salt, pepper and sugar. Stir in oil and pour it over the potatoes while still hot. Mix in beans and bacon. Wash the chives, cut into fine rolls and sprinkle over the salad. Cover and leave to stand for approx. 30 minutes. Flavour again.
Stir in oil and pour it over the potatoes while still hot. Mix in beans and bacon. Wash the chives, cut into fine rolls and sprinkle over the salad. Cover and leave to stand for approx. 30 minutes. Flavour again. Cut cheese into small pieces. Carefully fold into the salad and serve