Cut the tapioca into small pieces then put into an electric blender. Add just enough water and blend until fine. Remove and put tapioca pulp on a piece of clean muslin cloth. Squeeze out excess liquid.
Mix tapioca pulp, minced chicken and prawns, carrot and onion together in a mixing bowl. Add salt, pepper, black and white pepper, chilli powder and chicken stock granules. Mix well then add coriander leaves. Shape mixture into walnut-sized balls, then flatten them into patties.
Heat 2-3 tablespoons oil in a non-stick saucepan and pan-fry the patties in batches, turning them over occasionally until golden brown. Drain on crumpled paper towels and serve immediately.