Cut the meat into bite-size cubes and chop the onions. Heat the oil in a casserole dish and lightly fry themeat. Remove, then sauté the onions until golden yellow. Add the tomato paste and both paprika powders and pour on some water. Add the meat again, and stir in the bay leaf, garlic, caraway seeds, salt and pepper. Pour in some beef stock or water and stew for about 1 1/2 hours. After about 40 minutes, while the meat is stewing, add sauerkraut and if necessary, addwater or stock. (There should never be too much fluid, but just enough to cover the meat). As soon as the meat and sauerkraut are tender, combine the cream, sour cream and flour and stir until smooth. Add to the stew and stir well. Cook for another 10 minutes on medium heat, until the goulash is thick. Serve on warmed plates.