To make the broth, bring a large pot of water to a boil and salt it well. Add the 1 1/2 pounds salmon heads. When the water returns to a boil, let cook 1 minute. Remove the salmon bits (save them!) and discard the water. Blanching this way removes the scum from the stock and will give you a cleaner tasting broth when you are done.
Wipe out the pot, add 2 tablespoons olive oil, and turn the heat to medium-high. When the oil is hot, sauté the chopped 1 onion, 2 carrots, and 2 celery stalks, stirring often, until the onion is soft, about 4 to 5 minutes. Add 1 cup white wine, 2 bay leaves, and .88 ounce dried wild mushrooms* and use a wooden spoon to scrape up any browned bits from the bottom of the pot. Let the wine boil for a minute or two, then add the blanched salmon bones and enough cool water, at least 6 cups, and ensure it covers everything by about 1/2 inch. Bring to a very gentle simmer for 1-2 hours.
Line a strainer with a paper towel or cheesecloth. Set the strainer over a large bowl or pot and strain the broth. Discard the solids and reserve the broth.
To make the chowder, melt 1 tablespoon unsalted butter in a Dutch oven over medium heat. Add 1/4 pound thick bacon ends and pieces and cook, stirring and turning often, until crispy, about 10 minutes. Add 1 cup yellow onion(diced) and 2 celery stalks(diced) and sauté until soft, about 5 minutes. Add 1 1/2 pounds potatoes(peeled and diced) and 6 cups salmon broth and bring to a simmer. Cook until the potatoes are tender, about 15 to 20 minutes.
When the potatoes are tender, add 2 cups corn and 1 pound skinless boneless salmon meat. Cook gently until the salmon is just cooked through, about 5 minutes. Turn off the heat and stir in 1 small bunch fresh dill, 1 cup heavy cream and black pepper. Taste and add salt as desired. Serve at once.
If not serving the entire pot of soup, hold off on adding the heavy cream and store in an air tight container in the refrigerator. Do not add the heavy cream until ready to serve. This soup goes great with a crusty bread and a glass of white wine.
Notes
* I found a package at Trader Joes for $1.99 and it was a mix of Porcini, Shiitake, and Oyster Mushrooms