Clean the cabbage, carefully remove about 16 leaves from the cabbage. Use the rest of the cabbage for other purposes. Cook the cabbage leaves in portions in a large pot with boiling salted water for about 2 minutes. Remove the cabbage leaves, rinse in cold water and drain.
Knead minced meat, egg, breadcrumbs, mustard and tomato paste. Peel and finely dice the onion. Dice the cheese and mix it with the onions into the minced mass. Season with salt and pepper. Place cabbage leaves next to each other in portions, possibly cutting the thick vein of each leaf flatter. Form a total of about 16 dumplings from the minced mass and place 1 dumpling on each leaf. Fold in the cabbage edges and roll up. Wrap tightly with kitchen thread
Heat the oil in a pan. Fry the cabbage rolls in it for about 3 minutes, turning them over. Deglaze with broth. Cover and cook for about 45 minutes. Turn the cabbage rolls in between and add some water if necessary. Remove the cabbage rolls from the pan and keep warm. Stir the starch with 2 tbsp. water until smooth. Bring the stock to the boil again, stir in the starch and simmer for about 1 minute. Season to taste with salt and pepper. Remove the thread from the cabbage rolls. Arrange cabbage rolls and sauce. Boiled potatoes taste good with it