1In a large pot, boil beef shank in water with peppercorns.
2Skim off foam and simmer covered for 1.5 hours until tender.
3Add onion and corn, cook for 15 minutes.
4Add potatoes and green beans, simmer for 10 minutes.
5Add cabbage and cook for 5 more minutes.
6Season with fish sauce. Serve hot with rice and fish sauce on the side.
Use beef shank with bone for the most flavorful broth. Skim foam regularly while boiling.