I used potatoes & carrot also for this curry. We need loads of "chaaru" (gravy), so I've used 2 cups of coconut milk, you can adjust the qty to suit your taste. Also, if you don't prefer a creamy curry, you can use medium thick coconut milk instead of thick coconut milk. To enhance taste & also give a rich flavor, you can add cashew paste also. Mix the cashew paste in coconut milk & add to the curry. To make cashew paste, soak a small handful of cashews in hot water for 5-7 mins & grind them to a smooth paste.