Wash the potatoes and cook them covered in water for about 20 minutes. Then quench and peel.
Meanwhile peel the cucumbers, quarter them lengthwise and remove the seeds. Cut the cucumbers into pieces. Peel and chop onion. Heat 1 tablespoon of oil. Sauté onion and cucumber in it. Add good 1⁄8 l water and broth, bring to the boil.
Cover and cook for 8-10 minutes.
In the meantime, cut the potatoes in half and fry them in 2 tbsp. hot oil for about 15 minutes until golden brown. Season with salt and pepper. Wash and finely chop the dill. Stir the sour cream under the cucumbers. Season to taste with horseradish, salt and pepper.
Stir in the dill, keep warm.
Wash the salmon, dab dry and cut into 4 pieces. Season with salt and pepper. Heat 2 tablespoons of oil in a second pan. Fry the fish in it for about 3 minutes on each side until golden brown. Serve with cucumber vegetables and roast potatoes.