- Mix gram flour with water and whisk to make a lump free batter. Heat vegetable oil in a pan. Once the oil is hot, add mustard seeds, cumin seeds, hing and curry leaves and let them crackle for a few seconds. Add onion and green chillies and cook until onion turns translucent. Add tomatoes and cook for 2-3 minutes. Now add turmeric powder, red chilli powder, garam masala powder and salt to taste and cook for another minute. Add the besan mixture and cook on medium heat until the besan thickens. Add fresh coriander and mix well. Bombay chutney is ready to serve.