To make the fish stock, spread the fish bones on a baking sheet and season with salt. Let stand for 5 minutes, then rinse with cold water.

In a large stockpot, combine the vegetables, spices and herbs. Add the fish bones, cold water and wine, then add the ice. Bring to a simmer over medium heat and let simmer for 45 minutes; do not boil.

Remove the stock from the heat and let steep for 15 minutes. Strain the soup through a fine chinois. Add the kombu. Store in the refrigerator for up to a week, or the freezer for up to 1 month; remove the kombu before freezing. Makes about 2 quarts fish stock.

To make the soup, in a large pot over medium heat, cook the bacon, stirring often, just until crispy (bacon varies in cooking time depending on how it’s prepared and how thick it is, so keep a sharp eye), 3–6 minutes. Pour off all but about 1 tablespoon of bacon fat. Add the celery, fennel and onion and cook, stirring occasionally, until the celery is translucent, about 5 minutes.

Stir in the thyme and bay leaf. Add the beer and deglaze the pan, stirring to loosen any browned bits from the pan bottom, and cook until the liquid is reduced by about half, about 4 minutes. Add 2 quarts of the cold fish stock, potatoes, clams and bouquet garni (tying the herb bundle to the pot handle so it’s easier to retrieve later). Stir to combine.

Bring the chowder to a boil over high heat, then reduce the heat to medium-low and simmer uncovered until the potatoes are just tender, about 6 minutes. Remove from the heat. Stir in the salt and fish sauce. Add the kombu and let cool, then refrigerate overnight to develop the flavors.