Clean and wash the cabbage and cut the stalk out in a wedge shape. Cook the cabbage in plenty of boiling salted water for about 10 minutes.
Soak the rolls in cold water. Lift out cabbage. Remove 16 leaves bit by bit, if necessary cook the cabbage in salt water for 2-3 minutes. Cut the leaf veins flat.
Peel and finely chop the onion. Squeeze out the bread roll. Knead minced meat, egg and squeezed bread roll. Season with 1 1/2-2 teaspoons of salt, 1/2 teaspoon each of pepper and paprika and mustard. Form 8 oval dumplings from the minced mass with moistened hands.
Place 2 cabbage leaves slightly overlapping on top of each other and place 1 chopped dumpling in the middle of each. Fold the sides of the leaves towards the middle and roll them up firmly. Wrap the roulades with thread and tie them up.
Heat the lard in a casserole or small roaster. Fry the roulades in it on all sides over a high heat. Pour on 3/4 l water, stir in broth and tomato paste. Cover and stew for about 45 minutes.
Lift out the roulades. Boil the stock. Stir flour and 4 tablespoons of cold water until smooth and thicken the boiling stock with it. Season to taste with salt, pepper and sugar. Serve with parsley potatoes.