Wash 1 potato and cook for about 20 minutes. Boil the eggs hard. Rinse and peel both. Let cool off
Cut the potatoes into slices. Bring 1/4 l water, vinegar and stock to the boil. Peel, chop and add onion. Simmer for 1-2 minutes. Season with some salt and pepper. Pour hot over the potatoes. Leave to stand for about 15 minutes.
Mix yoghurt, crème fraîche, horseradish and a little salt. Add the capers to the potatoes. Leave to stand for at least 2 hours
Cut the eggs and salmon into small pieces. Wash the chives and chop finely. Fold everything into the salad. Season to taste
Drink: cool white wine or beer