In a large saucepan sweat the celery, carrots, onion and garlic until soft then add the potatoes.
Add the cream, milk and fish stock and bring to the boil, and then turn down and simmer until the potatoes are cooked.
Add the coriander, thyme, parsley and the raw seafood and cook for a further five minutes.
Thicken with the corn flour and season to taste. Remove from the heat and serve with home baked brown bread.
Note: Chowder is a meal in itself and can be made as a vegetable chowder or even a sweet corn and chicken chowder to name a few variations.