While chana is boiling, prepare the masala. Heat oil in kadhai at medium to high heat. Once it’s hot, reduce the heat to medium. Add cumin seeds as well as bay leaves and wait for the color to change. Add chopped onion, ginger & garlic paste, hing and a little salt. Saute the onion till golden color(for about 10-12 minutes). Add chopped tomatoes ( you can grind the tomato to make a puree), turmeric powder and saute it till tomato gets mushy.