2. Cut the mutton into pieces.
3. Wash carrots, peel and cut into pieces, shred onions and slice ginger.
4. Cold water in the mutton pot.
5. Bring to a boil with high fire, skim off the floating foam, add shredded ginger and scallion, and simmer 1 hour.
6. Add carrots for about 30 minutes.
7. Wash the yam, peel it, cut it into pieces and put it in the pot.
8. Cook for about 20 minutes.