Heat oil in kadai, add long sliced onion and cook until they are translucent
Add chopped tomatos, chilli powder, turmeric powder, garam masala, coriander powder
Add half cup water and cook until the tomatoes are soft
Add dahi in the masala and mix the sabji properly without any lumps. Add salt for taste and sugar
Cover kadai with lid and cook for another 2 min
Serve with hot fulkas/chapatis