In a pan or kadai heat oil. When it's hot add heeng, bay leaf, cinnamon stick, and Jeera/cumin seeds. Wait for cumin seeds to crackle. Add chopped green chili, grated ginger, red chili powder, and dhania powder. Now add chopped or pureed tomatoes and let it cook stirring frequently. when the tomato mixture starts leaving the oil or coming together it is ready.