1. Boil tomatoes till soft. (Microwave is useful for this)
2. Remove the shells and pureacute;e tomatoes in a grinder.
3. Add water to this pureacute;e as per the desired consistency. Also add salt and sugar and let it boil over medium heat.
4. Make a paste of green chilies, garlic and ginger.
5. Now, heat another small pan. Add 2-3 tsp ghee. When the ghee is heated, add cumin seeds, asafoetida, turmeric powder , curry leaves and chili-ginger-garlic paste. This is #39;tempering#39; (also called phodni in Marathi) for the saar.
6. When tomato pureacute;e starts boiling, pour the hot tempering over it. Stir well and simmer for 5 minutes.
Garnish with lots of coriander leaves and serve hot with rice.