Peel, wash and slice the potatoes. Heat some oil in a large pan and fry the potatoes for about 12 minutes, turning them until golden brown. Meanwhile clean and wash the leek and carrots. Cut the leek into slices. Cut the carrots in half lengthwise and cut them diagonally into pieces. Dice meat loaf. Season potatoes with salt and pepper and take them out of the pan.
Fry meat loaf briefly while turning and add to the potatoes. Braise vegetables in remaining oil and deglaze with broth. Simmer covered for 6-8 minutes. Wash parsley, dab dry and chop. Stir the mustard and sour cream into the vegetables and pour in the sauce thickener. Bring to the boil again briefly and season with salt and pepper. Add potatoes and meat loaf, warm up briefly and serve sprinkled with parsley