Wash the potatoes and cut in cubes. Boil the potatoes for 15-20 minutes in salted water. Drain and place in a bowl.
Finely chop the shallots, pickles/gherkins, red apple, and dill. Chop the smoked brown trout and the sun-dried tomatoes into smaller pieces.
In a small bowl mix the sour cream, mustard, chopped dill and 1 tablespoon of oil from the sun-dried tomatoes. Mix to combine. Season to taste with salt and pepper.
Add all the ingredients and the dressing to the potatoes and mix carefully. Season to taste with salt and pepper. Serve as a BBQ side dish.