1. Fry the curry paste for a minute then add the fish broth and coconut milk.
2. Bring to the boil then add fish sauce, the juice of 2 limes and red chilli.
3. Cut the cod into bitesize chunks. Add the cod to the curry along with the frozen soybeans, petit pois, and king prawns.
4. When the cod is cooked through and the prawns are pink, turn off the heat and stir in the spinach.
5. Serve over white rice.