Defrost the prawns if necessary. Wash the chives, shake dry and cut into fine rolls. Wash the lemon hot, dry and grate the peel thinly. Squeeze the lemon. Mix sour cream, horseradish, mustard, 1 tablespoon sugar, chives, 1-2 tablespoons lemon juice and zest. Season to taste with salt and pepper.
Wash and clean the cucumber, cut in half lengthwise and scrape out the core with a tablespoon. Clean and wash the bell peppers. Wash tomatoes, dice everything finely. Wash parsley, shake dry and chop finely. Mix vegetable cubes, parsley, 1 teaspoon sugar and the rest lemon juice. Season to taste with salt.
Peel the shrimps down to the caudal fin, make a longitudinal incision in the back and remove the intestines. Wash and dab dry. Toast bread in portions. Heat oil in a pan. Fry the prawns for about 3 minutes, turning them over. Season with salt and pepper. Arrange salad, horseradish cream, prawns and bread.