Fry the onions in hot oil until golden. Add paprika and stir well. Add the meat, cover and allow to simmer for 5 minutes. Add water or stock, tomato puree, salt, vinegar and marjoram. Cover saucepan and simmer on low heat for 3 to 3 1/2 hours, adding more water only if necessary. Serve with boiled potatoes, noodles or dumplings.