If the onions are big slit them into half without cutting through.
Heat oil in a non-stick pan, add onions.
Chop spring onion bulbs and add to the pan. Add bay leaf and mix well. Cover and cook for a couple of minutes. Remove the cover, stir the onions and cook till they are evenly brown all over.
Add tomato puree and 1 cup water and mix well. Cover and continue to cook for 5-7 minutes. Add salt and pepper powder and mix well. Cover and cook till the onions become soft.
Roughly chop parsley and add to the pan and mix well. Add castor sugar and mix well. Cover and cook for 2-3 minutes.
Roughly chop coriander sprigs and add and mix well. Cover and cook for 2-3 minutes.
Add raisins and mix well Add vinegar and mix well. Cover and cook on low heat for 20 minutes.
Transfer in a serving bowl and serve hot.