1. Wash and clean trotters.
2. Take a large saucepan (which can hold 5 pounds of cooked rice), put in the trotters, 2 whole garlic bulbs and enough water to cover them.
3. Boil on medium heat for about five to six hours.
4. During this process, if you see that water is not enough and trotters are not absolutely tender, put in some more boiling water, never put cold water, otherwise they will never become tender.
5. When they are tender and about 4 to 5 cups of soup is left, remove it from heat.
6. Discard all big bones, before discarding remove all the soft gelatine and bone marrow.
7. Keep this and small bones aside, strain all the soup through a fine sieve.
8. Put banaspati in the same saucepan and brown onions on medium heat.
9. Remove onions from banaspati and grind them. Mix onion paste, yogurt, salt and all dry spices, put them into the saucepan containing banaspati.
10. Keep stirring until all water of the yogurt dries, put trotters and soup in it.
11. Place the pan on heavy griddle (tava) and put it on low heat at least for an hour.
12. Remove from hat when the soup thickens. Add lemon juice.
13. Serve while it is hot, garnish with coriander leaves and green chilies.