If you are making the broth, do that first. Rinse your fish bones and heads under cold water. Remove the gills if they are still there; gills will turn a broth cloudy and make it bitter. Put the fish bones and other seafoody bits in a pot and cover with water by 1 inch. Bring to a simmer. Scum will rise to the top. Skim it off with a spoon. When the froth has subsided, drop the heat to a bare simmer, just a shimmy, really. Add the remaining ingredients and cook gently for 30 to 45 minutes. Strain and keep warm.

To make the fish chowder, heat the butter in a soup pot and cook the onion over medium heat until it turns translucent. Don't let the onions brown. Add the potatoes and cover with broth by about an inch and simmer gently until the potatoes are tender, about 15 to 20 minutes.

Add the fish and seafood, the sea beans and black pepper to taste. As these heat up, whisk the egg yolks with the heavy cream in a bowl. Using a ladle in one hand, and the whisk in another, slowly ladle some of the hot soup into the bowl with the egg-and-cream mixture -- all while whisking the mixture with the other hand. Repeat this two more times. What you are doing is tempering the egg yolks so they don't curdle. Add the contents of the bowl to the soup and stir to combine.

Add the dill and let everything heat through, but do not let the chowder boil, or it might separate and look nasty. Serve with good bread and either white wine or a nice beer.