Curry Paste: Grill the garlic, shallots and ginger until soft; about 20 minutes.
Pound all the ingredients in a stone mortar in the order given until a thick paste forms. If using chillies, add after shallots.
Curry: In a large saucepan fry the onions in the oil over medium heat until golden brown. Add the curry paste and the coconut cream; frying and stirring until all ingredients give off a good smell and the oil starts to separate from the coconut cream.
Add the chicken. Fry until done. Add the coconut milk, potatoes and carrots. Bring to a boil and simmer until the vegetables are soft, about 30 more minutes.