Pound together the garlic, salt, cilantro, paprika, cumin and cayenne. Stir in the lemon juice and olive oil. Marinate fish steaks or whole fish in this for several hours, turning from time to time.
Grill the fish for 4 minutes for each 1 cm thickness, turning halfway through. Baste with the marinade and serve at once, garnished with additional cilantro. Chill leftovers and serve cold the next day.
Notes: This picante, pungent Moroccan marinade can be used for any fish suitable for grilling or broiling and can also be used to marinate fish before baking. It's good with firm, white fleshed fish.