Stock

To complete the stock melt the butter in a thick-bottomed pan, then add the sliced onion and well-washed fish bones or carcass. Next add the bay leaf, parsley stalks, peppercorns, and lemon juice.

Place lid on the thick-bottomed pan and allow to sweat for 5mins ensuring no colouring takes place.

Now add the water and bring to the boil. Once this has come to the boil, skim any froth from the top and allow to simmer for 20mins.

Strain and save the liquid discarding the rest of the ingredients.

Roux

Put the milk in a heavy-based saucepan, place the studded onion in the milk and gently heat.

In a second thick-bottom pan melt the butter.

Once the butter has melted add the flour and cook until it produces a sandy texture.

Now slowly add the heated milk which when all the milk has been added will form a very thick white sauce.

Discard the onion at this stage. Now season with salt and pepper to your taste.

Soup

To complete the soup place the strained fish stock into a thick-bottomed saucepan and add the thick roux (sauce).

Gently bring to the boil while whisking periodically.

Adjust the seasoning to suit your taste with freshly ground black pepper and sea salt and add a generous serving of freshly chopped parsley.

You have now completed your oyster soup. For a more intense flavour add the juice from the oysters.

Now simply add as many oysters as you wish and serve with a little fresh runny cream.