Wash the potatoes and cook in plenty of boiling water for about 20 minutes. Rinse under cold water, drain and peel. Wash parsley, shake dry, pluck the leaves from the stalks and chop them except for something to garnish.
Mix salad cream, yoghurt and parsley. Season to taste with salt, pepper and vinegar. Wash and halve the tomatoes. Wash, clean and slice the cucumber. Cut potatoes into slices.
Add dressing, tomatoes and cucumber and carefully fold in. Heat the sausages in boiling, never boiling, water for about 5 minutes. Arrange salad on plates, garnish with parsley.
Carefully remove the sausages from the water, cut in half and arrange on the plates.