Wash potatoes thoroughly and cook in boiling water for about 20 minutes. Boil the eggs in boiling water for about 10 minutes until hard, rinse with cold water. Wash dill and parsley, shake dry. Pluck off leaves and chop finely. Wash and clean sorrel, shake dry, put some small leaves aside for decoration, chop the rest finely. Cut cress from the bed
Peel and finely chop the eggs. Set aside some of the herbs and chopped egg for garnishing. Mix the rest with yoghurt and sour cream. Season to taste with mustard, salt and pepper. Drain the potatoes and let them evaporate briefly. Arrange on plates with roast beef and sauce. Garnish with sorrel and sprinkle with herbs and egg