Cut fish into 2 inch pieces and set aside. Bring 2 cups water to a boil in a dutch oven or saucepan. Add salt and fish. Bring to a boil. Reduce heat and simmer, covered for 10-15 minutes. Drain fish,reserving liquid.
Meanwhile, cut onions and potatoes into thin slices and set aside. Put salt pork in a saucepan and cook over medium heat until crisp and brown. Remove salt pork with slotted spoon and set aside. Add onion and cook, turning until transparent. Remove onion. Add to fat in saucepan and heat butter. Blend in the mixture of flour, salt and spices. Heat until mixture bubbles. Remove from heat.
Add gradually while stirring the fish liquid and 3/4 cup of water. Add the potato and onion. Return to heat and simmer, stirring occasionally for about 10 minutes or until potatoes are tender. Stir in 1/2 cup milk and 1/3 cup cream. Simmer about 5 minutes longer. Do not boil.
Remove from heat. Stir in fish and heat on warm until ready to serve. Makes 2 quarts. Origin - New England.