A while back, i looked up this recipe from Internet as i was hoping to make the one i used to eat in SF fisherman's warf. unfortunately, this isn't the one but it's equally delicious. I have tried it out with added shrimp and scallops and sometimes clams. i use whatever white fish i have on hand. i have posted the original recipe below. you may make your own version based on this one.

ps: i haven't found Old Bay Seasoning here.

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Fish Chowder

2 pounds cod fillets, cubed
2 cups chopped onion
4 cups diced potatoes
4 fresh mushrooms, sliced
1 stalk celery, chopped
4 cups chicken broth
2 (12 ounce) cans evaporated milk
1 cup clam juice
1/2 cup all-purpose flour
salt to taste
ground black pepper to taste
1/8 teaspoon Old Bay Seasoning TM, or to taste
2 tablespoons butter

In a large stockpot, melt 2 tablespoons butter or margarine over medium heat. Add onions, mushrooms, and celery; saute until onions are transparent.
Add chicken stock and potatoes; simmer for 10 minutes.
Add fish, and simmer another 10 minutes.
Season to taste with seafood seasoning, salt, and pepper. Mix together clam juice and flour until smooth; stir into soup. Remove from heat, and stir in evaporated milk and remaining butter or margarine. Serve.