Heat oil in a Dutch oven and saute onions 3 minutes. Add cabbage and immediately pour vinegar over cabbage to prevent it from losing its red color. Sprinkle with salt and sugar. Add chopped apple or applesauce and a piece of salt pork. Pour in red wine and hot beef broth. Cover and simmer for 45 to 60 minutes. Cabbage should be just tender, not soft.
Shortly before end of cooking time, remove salt pork; cube and return it to the cabbage if desired. Correct seasonings and serve.