Soak rolls in cold water. Peel and chop the onion. Squeeze the bread well. Knead with minced meat, 1 egg, half of the onions and mustard. Season with salt and pepper. Form into an oval roast and place in the greased fat pan of the oven.
Sprinkle with pepper. Cook in the preheated oven (electric cooker: 175 °C/ convection oven: 150 °C/ gas: stage 2) for 1 1/4-1 1/2 hours. Cook potatoes in boiling water for about 15 minutes. For the sauce, boil 3 eggs in boiling water for about 10 minutes until hard, then rinse with cold water.
Stir the salad cream, yoghurt and lemon juice until smooth. Wash the herbs, dab dry, put some aside for garnishing. Finely chop remaining herbs, put some aside for garnishing, stir the rest into the sauce.
Season to taste with salt and pepper. Peel the eggs, cut 1 egg into slices. Chop the rest of the eggs coarsely and stir into the sauce. Drain potatoes, rinse with cold water and peel. Heat 2 tablespoons of oil and fry the potatoes until golden brown, turning them over.
Wash and clean the tomatoes and cut them into pieces. Mix with remaining onions, 2 tablespoons of oil and vinegar. Season to taste with salt and pepper. Season potatoes with salt. Serve roast with sauce, potatoes and tomato salad.
Serve garnished with set aside herbs and egg slices.