Cook slowly minced onion and garlic in melted fat until soft but not browned. Wash lettuce; tear into small pieces, add to onion mixture and cook about 10 min. Add salt, pepper, water and simmer 15 min. Add lemon juice and simmer 5 more min. Add lemon juice and simmer 5 more min. Beat yolk in a large serving bowl and add cream. Pour soup very slowly over egg mixture, stirring vigorously to prevent curdling. Do not cook again. Sprinkle Minced parsley on top. Serve with crackers or toast or hot corn meal mush(mamaliga).