For the potato salad, cook potatoes with skin in boiling water for about 20 minutes. Peel and finely dice onions. Wash chives, shake dry and cut into fine rolls. Cut bacon into strips and fry them crisply in a pan without fat.
Steam half the onions briefly. Deglaze with 1⁄4 l water, bring to the boil and stir in the stock. Stir in 6 tbsp vinegar. Season with 1 tablespoon sugar, salt and pepper. Remove from the stove. Rinse, peel and slice the potatoes.
Add chives to the hot marinade. Peel the cucumber, slice or cut it into thin slices and fold into the potato salad.
For the meatballs, rinse coalfish, dab dry and season with salt and pepper. Heat 1 tablespoon of oil, sauté the remaining onion in it. Place the pollack on top and cook covered for about 4 minutes. Cut smoked salmon into fine cubes.
Separate the egg. Roughly dismember coalfish. Loosely mix the whole fish, 2 tablespoons breadcrumbs, flour and egg white. Shape into approx. 8 meatballs, pressing them carefully into shape. Turn in remaining breadcrumbs.
Heat 2-3 tablespoons of oil in a large frying pan and fry the meatballs for about 4 minutes on each side until golden brown.
Meanwhile, for the honey mayonnaise, place the egg yolk, 4 tablespoons of vinegar, mustard, honey, 1⁄4 teaspoon salt and 100 ml oil in a tall, narrow mixing bowl. Mix with a hand blender to a mayonnaise and season to taste.
Dress everything.