Ox bone soup (Seolleongtang: 설렁탕)

Ox bone soup (Seolleongtang: 설렁탕)

Ingredients (for 6 servings):

 2½ pounds of ox bones, 2 pounds beef flank (or brisket or round), water,

Korean radish (or Daikon radish),

 onion, green onions, salt, black ground pepper, sesame oil.