Make the marinade by combining all the ingredients in a food processor or blender until well blended.
Season the rock cod generously with salt and pepper on both sides. Pour most of the marinade over the fish, reserve a couple of tablespoons to drizzle over the cooked fish. Marinate from 30 to 1 hour.
In a large skillet add the olive oil and sauté the fish for 3 minutes per side until golden.
Drizzle remaining marinade over the fish and garnish with parsley (optional)