In a food processor purée together coconut cream, desiccated coconut, cashews, brown sugar, chillies, coriander leaves, lime juice and zest, garlic, ginger, turmeric, cumin seeds, salt and stock. Transfer to a large pot. Simmer 10 minutes.
Peel potatoes and cut into 3cm cubes. Peel and de-seed the pumpkin. Cut into 3cm pieces. Slice fish into 3-4cm pieces.
Add potatoes and pumpkin and simmer gently for 20 minutes. Add fish fillets and stir well, cover and cook for 5 minutes without stirring until fish is cooked through. Spoon into serving bowls and top with lightly cooked green beans. Accompany with rice.
