Peel the cucumbers, cut them lengthwise in half and remove the seeds. Cut crosswise into strips. Peel onion and cut into fine cubes. Season minced meat with salt and pepper and knead with breadcrumbs, egg and onion.
Form 16-20 meatballs. Heat oil and fry meatballs all around for about 6 minutes. In the meantime heat up fat in a second pan. Stew cucumber for about 6 minutes. After 4 minutes stir in sour cream and horseradish.
Season to taste with salt and pepper. Wash the dill, shake dry, pluck the dill flags from the stems and cut finely. Arrange the cucumber pan with dill and meatballs. Bread tastes good with it.