Cut cauliflower into small florets. Cube potatoes. Chop onions, grate ginger and cut chillies small.
Add oil in pan. Add cumin seeds, black cumin seeds, a pinch hing, 2 to 3 bay leaves and turmeric.
When cumin splutters add onions, ginger and chillies. Add salt, and roast till onions become translucent.
Add a dash of cumin and coriander powder. Add cauliflower and potatoes and combine well.
Cover and cook stirring occasionally till vegetable are cooked. Garnish with coriander.