Sweat the vegetables: Melt the butter in a large, heavy-bottomed pot over a medium heat. Add the diced onion and celery, stirring frequently. After about 6-8 minutes, the onion will turn translucent and glossy, and the kitchen will smell sweet and savoury. The celery should have softened but not browned—you’re looking for a pale, golden sheen, not colour.

Bloom the aromatics: Stir in the minced garlic and smoked paprika. Cook for 30 seconds until the garlic is fragrant—you’ll smell a warm, smoky note rising from the pot. Immediately add the flour and stir vigorously for a full minute. The mixture will look like a thick, golden paste and will pull away from the sides of the pot.

Build the base: Pour in the fish stock in a steady stream, whisking constantly to prevent lumps. The liquid will hiss and steam as it hits the hot pan. Continue whisking until the mixture is smooth and begins to thicken slightly, about 2 minutes. The colour will turn a pale, creamy beige.

Cook the potatoes: Add the milk, single cream, bay leaf, and potato cubes. Stir everything together, then bring the chowder to a gentle simmer—you should see small bubbles breaking the surface, not a rolling boil. Reduce the heat to low, partially cover, and let it cook for 15-18 minutes. The potatoes should be fork-tender when pierced, and the liquid will have thickened into a creamy, opaque broth.

Add the fish: Gently slide the white fish chunks into the pot, nestling them into the hot liquid. Let them cook undisturbed for 3 minutes. You’ll see the edges of the fish turn opaque white and the flesh flake easily when prodded with a fork. The chowder will release a delicate, sweet fish aroma.

Finish with shellfish: Stir in the prawns and mussels (or clams). Cook for 2-3 minutes more. The prawns will curl slightly and turn a vibrant pink, and the mussels will have heated through. If using clams in shells, cover the pot and cook until all shells have opened wide—discard any that remain closed after 5 minutes.

Season and serve: Remove the pot from the heat. Discard the bay leaf. Stir in the chopped parsley, then taste the chowder—the colour should be a warm, creamy ivory flecked with green. Season with salt and pepper, remembering that the seafood and stock already carry some saltiness. Ladle into warm bowls and serve immediately.