Peel potatoes, grate coarsely, squeeze well. Stir in egg and season with salt and pepper. Rinse salmon, dab dry and also season with salt and pepper. Spread the potato mixture on the salmon and press it down well.
Heat the oil in an ovenproof pan, place the salmon with the potato side in and fry until golden brown. Turn the fillet and cook in the preheated oven (electric cooker: 200 °C/ gas: level 3) for approx. 10 minutes.
In the meantime, peel the cucumber. With a peeler pull down long strips all around until the seeds are visible. Clean, wash and cut the peppers into rhombs. Whip yoghurt, salt, pepper and lemon juice with a hand blender until foamy.
Wash the dill, dab dry and chop finely, stir into the yoghurt foam. Cut fish fillet into thick slices and place on plates. Lightly salt the cucumber strips, mix with the paprika and also spread on the plates, drizzle with yoghurt sauce.
Garnish with one dill branch each.