For the cabbage cut the pork shoulder into cubes of about 3-4 cm. Peel the onions, cut into thin slices and roast in fat over low heat for about 25 minutes until light brown.
Briefly fry the tomato puree, stir in the paprika powder and immediately deglaze with a little water. Add meat, pour in stock, season with cumin, pepper, garlic and bay leaf and simmer over medium heat for about 40 minutes, half covered.
In the meantime, wash sauerkraut if necessary, squeeze well and cut coarsely. Wash and clean the peppers, cut into small pieces and add to the goulash with the sauerkraut.
Steam goulash on low heat for another 40 minutes, then add salt. Wash and peel raw potato, grate finely, add, cook cabbage for another 10 minutes at low heat. Remove bay leaf. Season to taste with salt.