Heat oil in a large saucepan over medium heat; stir in onions and bay leaves, and cook about 5 minutes until the onions begin to soften. Add flour, ginger-garlic paste, garam masala, turmeric, and Indian chili powder. Cook and stir until fragrant, about 1 minute.
Pour the water into the pan, and bring to a boil while scraping the browned bits of food off of the bottom with a wooden spoon. Pour in the tomato puree and thin with additional water to desired consistency. Add sugar and salt; cook until sugar is dissolved and soup is hot, about 5 minutes.
Remove bay leaves and serve with cream if desired.
