Saute the onions with the salt pork on low for about 10 - 15 minutes. Remove the onions and salt pork to a plate but reserve the liquid pork fat.
Add the haddock to the same pan and cover with evaporated milk, whole milk and water. Simmer on low for 5 min. Remove fish carefully so as not to break it up.
Add the cubed potatoes to milk and fish broth. Cook until almost done.
Combine all ingredients (except pork fat) together in a large pan.
Add salt and pepper to taste with 1-2 T. pork fat and 1-2 T. butter.
Add half and half or cream-enough to cover and then some.
Cook on low to heat well. Don’t allow to boil. Best if it sets for a day.