In a large sauce pot, melt butter and sauté celery, onion, and carrot for 3–4 minutes. Add flour and incorporate into vegetables; add diced potato and broth (depending on the fish you are using) and simmer. While broth is simmering, poach fish in another pan until flakey. When vegetables are tender, flake fish and add to broth. Simmer for 5 more minutes; salt and pepper to taste and serve.
Cooks note: This is a very easy recipe to make and just as easy to change to make to your taste. Cod, halibut, northern pike, or a mixture thereof work well in this recipe. Recipe makes about 1 quart of chowder.