Clean the fish fillet, acidify it, season with salt, let it simmer in a little salted water for about 5 minutes, then drain and chop it apart. Mix with the kohlrabi strips, carrot wedges and peas.
Mix the mayonnaise with the condensed milk until creamy, fold in the fish-vegetable mixture and the chives, season with salt and pepper and serve the salad garnished with parsley.