Place the coriander in a blender along with all the other ingredients up to and including the ground cardamom, puree until smooth.
Season the fish fillets then place each fish fillet between 4 slices of lemon and make a parcel out of each using kitchen twine, brush with oil.
Grill the fish over/on a medium heat (approx. 200 °C for approx. 7 mins. on each side. Plate up the fish with the lemon slices and sauce.