Prepare the cod by cutting it into pieces and leaving it to soak overnight for 12 hours.
After soaking the cod overnight scrape off the scales and put the pieces in a pan of cold water
Place the pan over a medium heat then just before boiling point remove the pieces of cod - drain off the water - remove any bones from the cod at this point
Put 200ml of the oil in a strong earthenware casserole dish and then slice 4 garlic cloves finely - heat the oil and fry the sliced garlic, when it turns golden brown remove the garlic from the oil and set aside for later
Add the prepared pieces of cod (skin side up) and the stock to the casserole dish and continue cooking over a medium heat - move the dish from side to side now and then to prevent the fish from sticking
Meanwhile in a frying pan heat the rest of the oil and 2 cloves of sliced garlic until the garlic turns golden brown
Add the rest of the oil and garlic to the contents of the casserole dish a little at a time
Finally when the sauce has thickened put the fried garlic slices on top of the contents of the casserole dish and garnish with a little chopped fresh parsley - serve straight from the casserole dish