This recipe is entirely my own. I created it last year to use up the trim (backs, tails, fins, cheeks, etc.) from two very large Copper River King salmons. It's a very Northwest chowder, and has received raves from everyone who has tasted it. It also makes a LOT of chowder; you will have leftovers for days, or enough to feed a party. Tips: You will need two heavy 8-quart or larger stockpots for this, unless you have a heavy one at least 16-20 quarts in size. I recommend allowing one day to cook the stock and one day to make the chowder rather than trying to do it all at once, because long, slow simmering really brings out all the flavors here. An oloroso sherry may be substituted for the Madeira. The butter may be omitted and skim or low-fat milk substituted for the half and half if you want a lower-fat version. Do not defat the stock. The stock fat is rich in beneficial Omega-3s and much of the taste of the chowder depends on the oiliness and flavor unique to Copper River King salmon. If using other wild fish, defat the stock or not as you prefer. I strongly recommend using only wild fish for this recipe. You may be able to obtain salmon trim at no charge if you live on the West Coast of the U.S. and know a fishmonger. Kids love the taste, even though it contains lots of fish. We've tried it on a three-year-old and a six-year-old. Don't be daunted by the number of ingredients, the number of steps, or the fact that it takes two days to make this. It's actually *really* easy; the hardest parts are chopping the vegetables and picking the meat off the bones.