Heat butter in heavy sauce pan, brown beef cubes and remove. Add flour and cook while stirring until roux is medium brown. Add onions, celery, carrots and garlic and cook for 5 minutes until soft. Add meat and all remaining ingredients except eggs, green onions and sherry. Stir to blend and simmer until meat is very tender, about 1-1/2 hours, add a little water if needed during cooking. Taste for salt and pepper and, if desired, Tabasco. Add eggs and cook for 5 more minutes. Garnish with green onions and pass the sherry.