Chop the bacon into small cubes, fry briefly in oil. Add the finely chopped onion, let it soften, remove from the stove and stir in the paprika powder after a minute. Add tomato paste and pour on the soup. Cut the cabbage into tender strips and add to the soup. Cook gently with all the spices for approx. 25 minutes.
Mix the sour cream with the flour until smooth, use the whisk to quickly mix into the soup. Boil briefly and season to taste.