Put dhal into a saucepan, add more than enough water to boil. Reduce the heat and simmer. Halfway through, add chicken and continue to cook for 30 minutes or until dhal is soft and chicken is tender.
Heat oil in a pot. Add spices (A) and fry for 1-2 minutes. Add in (B) and (C) and continue to fry until fragrant. Put in carrot, potato and thin coconut milk. Bring to a simmering boil.
Put dhal and chicken into the pot, add in long beans, chillies and the remaining thin coconut milk. Continue to cook for 10-15 minutes. Add thick coconut milk, salt and sugar to taste. Cook for another 2-3 minutes. Dish out and serve.